This is the command virsh that can be run in the OnWorks free hosting provider using one of our multiple free online workstations such as Ubuntu Online, Fedora Online, Windows online emulator or MAC OS online emulator
PROGRAM:
NAME
virsh - management user interface
SYNOPSIS
virsh [OPTION]... [COMMAND_STRING]
virsh [OPTION]... COMMAND [ARG]...
DESCRIPTION
The virsh program is the main interface for managing virsh guest domains. The program can
be used to create, pause, and shutdown domains. It can also be used to list current
domains. Libvirt is a C toolkit to interact with the virtualization capabilities of recent
versions of Linux (and other OSes). It is free software available under the GNU Lesser
General Public License. Virtualization of the Linux Operating System means the ability to
run multiple instances of Operating Systems concurrently on a single hardware system where
the basic resources are driven by a Linux instance. The library aims at providing a long
term stable C API. It currently supports Xen, QEMU, KVM, LXC, OpenVZ, VirtualBox and
VMware ESX.
The basic structure of most virsh usage is:
virsh [OPTION]... <command> <domain> [ARG]...
Where command is one of the commands listed below; domain is the numeric domain id, or the
domain name, or the domain UUID; and ARGS are command specific options. There are a few
exceptions to this rule in the cases where the command in question acts on all domains,
the entire machine, or directly on the xen hypervisor. Those exceptions will be clear for
each of those commands. Note: it is permissible to give numeric names to domains,
however, doing so will result in a domain that can only be identified by domain id. In
other words, if a numeric value is supplied it will be interpreted as a domain id, not as
a name.
The virsh program can be used either to run one COMMAND by giving the command and its
arguments on the shell command line, or a COMMAND_STRING which is a single shell argument
consisting of multiple COMMAND actions and their arguments joined with whitespace, and
separated by semicolons between commands. Within COMMAND_STRING, virsh understands the
same single, double, and backslash escapes as the shell, although you must add another
layer of shell escaping in creating the single shell argument. If no command is given in
the command line, virsh will then start a minimal interpreter waiting for your commands,
and the quit command will then exit the program.
The virsh program understands the following OPTIONS.
-c, --connect URI
Connect to the specified URI, as if by the connect command, instead of the default
connection.
-d, --debug LEVEL
Enable debug messages at integer LEVEL and above. LEVEL can range from 0 to 4
(default). See the documentation of VIRSH_DEBUG environment variable below for the
description of each LEVEL.
-e, --escape string
Set alternative escape sequence for console command. By default, telnet's ^] is used.
Allowed characters when using hat notation are: alphabetic character, @, [, ], \, ^,
_.
-h, --help
Ignore all other arguments, and behave as if the help command were given instead.
-k, --keepalive-interval INTERVAL
Set an INTERVAL (in seconds) for sending keepalive messages to check whether
connection to the server is still alive. Setting the interval to 0 disables client
keepalive mechanism.
-K, --keepalive-count COUNT
Set a number of times keepalive message can be sent without getting an answer from the
server without marking the connection dead. There is no effect to this setting in
case the INTERVAL is set to 0.
-l, --log FILE
Output logging details to FILE.
-q, --quiet
Avoid extra informational messages.
-r, --readonly
Make the initial connection read-only, as if by the --readonly option of the connect
command.
-t, --timing
Output elapsed time information for each command.
-v, --version[=short]
Ignore all other arguments, and prints the version of the libvirt library virsh is
coming from
-V, --version=long
Ignore all other arguments, and prints the version of the libvirt library virsh is
coming from and which options and driver are compiled in.
NOTES
Most virsh operations rely upon the libvirt library being able to connect to an already
running libvirtd service. This can usually be done using the command invoke-rc.d libvirtd
start.
Most virsh commands require root privileges to run due to the communications channels used
to talk to the hypervisor. Running as non root will return an error.
Most virsh commands act synchronously, except maybe shutdown, setvcpus and setmem. In
those cases the fact that the virsh program returned, may not mean the action is complete
and you must poll periodically to detect that the guest completed the operation.
virsh strives for backward compatibility. Although the help command only lists the
preferred usage of a command, if an older version of virsh supported an alternate spelling
of a command or option (such as --tunnelled instead of --tunneled), then scripts using
that older spelling will continue to work.
Several virsh commands take an optionally scaled integer; if no scale is provided, then
the default is listed in the command (for historical reasons, some commands default to
bytes, while other commands default to kibibytes). The following case-insensitive
suffixes can be used to select a specific scale:
b, byte byte 1
KB kilobyte 1,000
k, KiB kibibyte 1,024
MB megabyte 1,000,000
M, MiB mebibyte 1,048,576
GB gigabyte 1,000,000,000
G, GiB gibibyte 1,073,741,824
TB terabyte 1,000,000,000,000
T, TiB tebibyte 1,099,511,627,776
PB petabyte 1,000,000,000,000,000
P, PiB pebibyte 1,125,899,906,842,624
EB exabyte 1,000,000,000,000,000,000
E, EiB exbibyte 1,152,921,504,606,846,976
GENERIC COMMANDS
The following commands are generic i.e. not specific to a domain.
help [command-or-group]
This lists each of the virsh commands. When used without options, all commands are
listed, one per line, grouped into related categories, displaying the keyword for each
group.
To display only commands for a specific group, give the keyword for that group as an
option. For example:
virsh # help host
Host and Hypervisor (help keyword 'host'):
capabilities capabilities
cpu-models show the CPU models for an architecture
connect (re)connect to hypervisor
freecell NUMA free memory
hostname print the hypervisor hostname
qemu-attach Attach to existing QEMU process
qemu-monitor-command QEMU Monitor Command
qemu-agent-command QEMU Guest Agent Command
sysinfo print the hypervisor sysinfo
uri print the hypervisor canonical URI
To display detailed information for a specific command, give its name as the option
instead. For example:
virsh # help list
NAME
list - list domains
SYNOPSIS
list [--inactive] [--all]
DESCRIPTION
Returns list of domains.
OPTIONS
--inactive list inactive domains
--all list inactive & active domains
quit, exit
quit this interactive terminal
version [--daemon]
Will print out the major version info about what this built from. If --daemon is
specified then the version of the libvirt daemon is included in the output.
Example
$ virsh version
Compiled against library: libvirt 1.2.3
Using library: libvirt 1.2.3
Using API: QEMU 1.2.3
Running hypervisor: QEMU 2.0.50
$ virsh version --daemon
Compiled against library: libvirt 1.2.3
Using library: libvirt 1.2.3
Using API: QEMU 1.2.3
Running hypervisor: QEMU 2.0.50
Running against daemon: 1.2.6
cd [directory]
Will change current directory to directory. The default directory for the cd command
is the home directory or, if there is no HOME variable in the environment, the root
directory.
This command is only available in interactive mode.
pwd Will print the current directory.
connect [URI] [--readonly]
(Re)-Connect to the hypervisor. When the shell is first started, this is automatically
run with the URI parameter requested by the "-c" option on the command line. The URI
parameter specifies how to connect to the hypervisor. The documentation page at
<http://libvirt.org/uri.html> list the values supported, but the most common are:
xen:///
this is used to connect to the local Xen hypervisor
qemu:///system
connect locally as root to the daemon supervising QEMU and KVM domains
qemu:///session
connect locally as a normal user to his own set of QEMU and KVM domains
lxc:///
connect to a local linux container
To find the currently used URI, check the uri command documented below.
For remote access see the documentation page at <http://libvirt.org/uri.html> on how
to make URIs. The --readonly option allows for read-only connection
uri Prints the hypervisor canonical URI, can be useful in shell mode.
hostname
Print the hypervisor hostname.
sysinfo
Print the XML representation of the hypervisor sysinfo, if available.
nodeinfo
Returns basic information about the node, like number and type of CPU, and size of the
physical memory. The output corresponds to virNodeInfo structure. Specifically, the
"CPU socket(s)" field means number of CPU sockets per NUMA cell. The information
libvirt displays is dependent upon what each architecture may provide.
nodecpumap [--pretty]
Displays the node's total number of CPUs, the number of online CPUs and the list of
online CPUs.
With --pretty the online CPUs are printed as a range instead of a list.
nodecpustats [cpu] [--percent]
Returns cpu stats of the node. If cpu is specified, this will prints specified cpu
statistics only. If --percent is specified, this will prints percentage of each kind
of cpu statistics during 1 second.
nodememstats [cell]
Returns memory stats of the node. If cell is specified, this will prints specified
cell statistics only.
nodesuspend [target] [duration]
Puts the node (host machine) into a system-wide sleep state and schedule the node's
Real-Time-Clock interrupt to resume the node after the time duration specified by
duration is out. target specifies the state to which the host will be suspended to,
it can be "mem" (suspend to RAM), "disk" (suspend to disk), or "hybrid" (suspend to
both RAM and disk). duration specifies the time duration in seconds for which the
host has to be suspended, it should be at least 60 seconds.
node-memory-tune [shm-pages-to-scan] [shm-sleep-millisecs] [shm-merge-across-nodes]
Allows you to display or set the node memory parameters. shm-pages-to-scan can be
used to set the number of pages to scan before the shared memory service goes to
sleep; shm-sleep-millisecs can be used to set the number of millisecs the shared
memory service should sleep before next scan; shm-merge-across-nodes specifies if
pages from different numa nodes can be merged. When set to 0, only pages which
physically reside in the memory area of same NUMA node can be merged. When set to 1,
pages from all nodes can be merged. Default to 1.
Note: Currently the "shared memory service" only means KSM (Kernel Samepage Merging).
capabilities
Print an XML document describing the capabilities of the hypervisor we are currently
connected to. This includes a section on the host capabilities in terms of CPU and
features, and a set of description for each kind of guest which can be virtualized.
For a more complete description see:
<http://libvirt.org/formatcaps.html> The XML also show the NUMA topology information
if available.
domcapabilities [virttype] [emulatorbin] [arch] [machine]
Print an XML document describing the domain capabilities for the hypervisor we are
connected to using information either sourced from an existing domain or taken from
the virsh capabilities output. This may be useful if you intend to create a new domain
and are curious if for instance it could make use of VFIO by creating a domain for the
hypervisor with a specific emulator and architecture.
Each hypervisor will have different requirements regarding which options are required
and which are optional. A hypervisor can support providing a default value for any of
the options.
The virttype option specifies the virtualization type used. The value to be used is
either from the 'type' attribute of the <domain/> top level element from the domain
XML or the 'type' attribute found within each <guest/> element from the virsh
capabilities output. The emulatorbin option specifies the path to the emulator. The
value to be used is either the <emulator> element in the domain XML or the virsh
capabilities output. The arch option specifies the architecture to be used for the
domain. The value to be used is either the "arch" attribute from the domain's XML
<os/> element and <type/> subelement or the "name" attribute of an <arch/> element
from the virsh capabililites output. The machine specifies the machine type for the
emulator. The value to be used is either the "machine" attribute from the domain's XML
<os/> element and <type/> subelement or one from a list of machines from the virsh
capabilities output for a specific architecture and domain type.
For the qemu hypervisor, a virttype of either 'qemu' or 'kvm' must be supplied along
with either the emulatorbin or arch in order to generate output for the default
machine. Supplying a machine value will generate output for the specific machine.
inject-nmi domain
Inject NMI to the guest.
list [--inactive | --all] [--managed-save] [--title] { [--table] | --name | --uuid }
[--persistent] [--transient] [--with-managed-save] [--without-managed-save] [--autostart]
[--no-autostart] [--with-snapshot] [--without-snapshot] [--state-running] [--state-paused]
[--state-shutoff] [--state-other]
Prints information about existing domains. If no options are specified it prints out
information about running domains.
An example format for the list is as follows:
virsh list
Id Name State
----------------------------------------------------
0 Domain-0 running
2 fedora paused
Name is the name of the domain. ID the domain numeric id. State is the run state
(see below).
STATES
The State field lists 8 states for a domain, and which ones the current domain is in.
running
The domain is currently running on a CPU
idle
The domain is idle, and not running or runnable. This can be caused because the
domain is waiting on IO (a traditional wait state) or has gone to sleep because
there was nothing else for it to do.
paused
The domain has been paused, usually occurring through the administrator running
virsh suspend. When in a paused state the domain will still consume allocated
resources like memory, but will not be eligible for scheduling by the hypervisor.
shutdown
The domain is in the process of shutting down, i.e. the guest operating system has
been notified and should be in the process of stopping its operations gracefully.
shut off
The domain is not running. Usually this indicates the domain has been shut down
completely, or has not been started.
crashed
The domain has crashed, which is always a violent ending. Usually this state can
only occur if the domain has been configured not to restart on crash.
dying
The domain is in process of dying, but hasn't completely shutdown or crashed.
pmsuspended
The domain has been suspended by guest power management, e.g. entered into s3
state.
Normally only active domains are listed. To list inactive domains specify --inactive
or --all to list both active and inactive domains.
To further filter the list of domains you may specify one or more of filtering flags
supported by the list command. These flags are grouped by function. Specifying one or
more flags from a group enables the filter group. Note that some combinations of flags
may yield no results. Supported filtering flags and groups:
Persistence
Flag --persistent is used to include persistent domains in the returned list. To
include transient domains specify --transient.
Existence of managed save image
To list domains having a managed save image specify flag --with-managed-save. For
domains that don't have a managed save image specify --without-managed-save.
Domain state
The following filter flags select a domain by its state: --state-running for
running domains, --state-paused for paused domains, --state-shutoff for turned
off domains and --state-other for all other states as a fallback.
Autostarting domains
To list autostarting domains use the flag --autostart. To list domains with this
feature disabled use --no-autostart.
Snapshot existence
Domains that have snapshot images can be listed using flag --with-snapshot,
domains without a snapshot --without-snapshot.
When talking to older servers, this command is forced to use a series of API calls
with an inherent race, where a domain might not be listed or might appear more than
once if it changed state between calls while the list was being collected. Newer
servers do not have this problem.
If --managed-save is specified, then domains that have managed save state (only
possible if they are in the shut off state, so you need to specify --inactive or --all
to actually list them) will instead show as saved in the listing. This flag is usable
only with the default --table output. Note that this flag does not filter the list of
domains.
If --name is specified, domain names are printed instead of the table formatted one
per line. If --uuid is specified domain's UUID's are printed instead of names. Flag
--table specifies that the legacy table-formatted output should be used. This is the
default. All of these are mutually exclusive.
If --title is specified, then the short domain description (title) is printed in an
extra column. This flag is usable only with the default --table output.
Example:
virsh list --title
Id Name State Title
--------------------------------------------------------------------------
0 Domain-0 running Mailserver 1
2 fedora paused
freecell [{ [--cellno] cellno | --all }]
Prints the available amount of memory on the machine or within a NUMA cell. The
freecell command can provide one of three different displays of available memory on
the machine depending on the options specified. With no options, it displays the
total free memory on the machine. With the --all option, it displays the free memory
in each cell and the total free memory on the machine. Finally, with a numeric
argument or with --cellno plus a cell number it will display the free memory for the
specified cell only.
freepages [{ [--cellno] cellno [--pagesize] pagesize | --all }]
Prints the available amount of pages within a NUMA cell. cellno refers to the NUMA
cell you're interested in. pagesize is a scaled integer (see NOTES above).
Alternatively, if --all is used, info on each possible combination of NUMA cell and
page size is printed out.
allocpages [--pagesize] pagesize [--pagecount] pagecount [[--cellno] cellno] [--add]
[--all]
Change the size of pages pool of pagesize on the host. If --add is specified, then
pagecount pages are added into the pool. However, if --add wasn't specified, then the
pagecount is taken as the new absolute size of the pool (this may be used to free some
pages and size the pool down). The cellno modifier can be used to narrow the
modification down to a single host NUMA cell. On the other end of spectrum lies --all
which executes the modification on all NUMA cells.
cpu-baseline FILE [--features] [--migratable]
Compute baseline CPU which will be supported by all host CPUs given in <file>. The
list of host CPUs is built by extracting all <cpu> elements from the <file>. Thus, the
<file> can contain either a set of <cpu> elements separated by new lines or even a set
of complete <capabilities> elements printed by capabilities command. If --features is
specified then the resulting XML description will explicitly include all features that
make up the CPU, without this option features that are part of the CPU model will not
be listed in the XML description. If --migratable is specified, features that block
migration will not be included in the resulting CPU.
cpu-compare FILE [--error]
Compare CPU definition from XML <file> with host CPU. The XML <file> may contain
either host or guest CPU definition. The host CPU definition is the <cpu> element and
its contents as printed by capabilities command. The guest CPU definition is the <cpu>
element and its contents from domain XML definition. For more information on guest CPU
definition see: <http://libvirt.org/formatdomain.html#elementsCPU>. If --error is
specified, the command will return an error when the given CPU is incompatible with
host CPU and a message providing more details about the incompatibility will be
printed out.
cpu-models arch
Print the list of CPU models known for the specified architecture.
echo [--shell] [--xml] [arg...]
Echo back each arg, separated by space. If --shell is specified, then the output will
be single-quoted where needed, so that it is suitable for reuse in a shell context.
If --xml is specified, then the output will be escaped for use in XML.
DOMAIN COMMANDS
The following commands manipulate domains directly, as stated previously most commands
take domain as the first parameter. The domain can be specified as a short integer, a name
or a full UUID.
autostart [--disable] domain
Configure a domain to be automatically started at boot.
The option --disable disables autostarting.
console domain [devname] [--safe] [--force]
Connect the virtual serial console for the guest. The optional devname parameter
refers to the device alias of an alternate console, serial or parallel device
configured for the guest. If omitted, the primary console will be opened.
If the flag --safe is specified, the connection is only attempted if the driver
supports safe console handling. This flag specifies that the server has to ensure
exclusive access to console devices. Optionally the --force flag may be specified,
requesting to disconnect any existing sessions, such as in a case of a broken
connection.
create FILE [--console] [--paused] [--autodestroy] [--pass-fds N,M,...]
Create a domain from an XML <file>. An easy way to create the XML <file> is to use the
dumpxml command to obtain the definition of a pre-existing guest. The domain will be
paused if the --paused option is used and supported by the driver; otherwise it will
be running. If --console is requested, attach to the console after creation. If
--autodestroy is requested, then the guest will be automatically destroyed when virsh
closes its connection to libvirt, or otherwise exits.
If --pass-fds is specified, the argument is a comma separated list of open file
descriptors which should be pass on into the guest. The file descriptors will be re-
numbered in the guest, starting from 3. This is only supported with container based
virtualization.
Example
virsh dumpxml <domain> > domain.xml
vi domain.xml (or make changes with your other text editor)
virsh create domain.xml
define FILE
Define a domain from an XML <file>. The domain definition is registered but not
started. If domain is already running, the changes will take effect on the next boot.
desc domain [[--live] [--config] | [--current]] [--title] [--edit] [--new-desc New
description or title message]
Show or modify description and title of a domain. These values are user fields that
allow to store arbitrary textual data to allow easy identification of domains. Title
should be short, although it's not enforced. (See also metadata that works with XML
based domain metadata.)
Flags --live or --config select whether this command works on live or persistent
definitions of the domain. If both --live and --config are specified, the --config
option takes precedence on getting the current description and both live configuration
and config are updated while setting the description. --current is exclusive and
implied if none of these was specified.
Flag --edit specifies that an editor with the contents of current description or title
should be opened and the contents saved back afterwards.
Flag --title selects operation on the title field instead of description.
If neither of --edit and --new-desc are specified the note or description is displayed
instead of being modified.
destroy domain [--graceful]
Immediately terminate the domain domain. This doesn't give the domain OS any chance
to react, and it's the equivalent of ripping the power cord out on a physical machine.
In most cases you will want to use the shutdown command instead. However, this does
not delete any storage volumes used by the guest, and if the domain is persistent, it
can be restarted later.
If domain is transient, then the metadata of any snapshots will be lost once the guest
stops running, but the snapshot contents still exist, and a new domain with the same
name and UUID can restore the snapshot metadata with snapshot-create.
If --graceful is specified, don't resort to extreme measures (e.g. SIGKILL) when the
guest doesn't stop after a reasonable timeout; return an error instead.
domblkstat domain [block-device] [--human]
Get device block stats for a running domain. A block-device corresponds to a unique
target name (<target dev='name'/>) or source file (<source file='name'/>) for one of
the disk devices attached to domain (see also domblklist for listing these names). On
a lxc or qemu domain, omitting the block-device yields device block stats summarily
for the entire domain.
Use --human for a more human readable output.
Availability of these fields depends on hypervisor. Unsupported fields are missing
from the output. Other fields may appear if communicating with a newer version of
libvirtd.
Explanation of fields (fields appear in the following order):
rd_req - count of read operations
rd_bytes - count of read bytes
wr_req - count of write operations
wr_bytes - count of written bytes
errs - error count
flush_operations - count of flush operations
rd_total_times - total time read operations took (ns)
wr_total_times - total time write operations took (ns)
flush_total_times - total time flush operations took (ns)
<-- other fields provided by hypervisor -->
domifaddr domain [interface] [--full] [--source lease|agent]
Get a list of interfaces of a running domain along with their IP and MAC addresses, or
limited output just for one interface if interface is specified. Note that interface
can be driver dependent, it can be the name within guest OS or the name you would see
in domain XML. Moreover, the whole command may require a guest agent to be configured
for the queried domain under some drivers, notably qemu. If --full is specified, the
interface name is always displayed when the interface has multiple addresses or alias,
otherwise it only displays the interface name for the first address, and "-" for the
others. The --source argument specifies what data source to use for the addresses,
currently one of 'lease' to read DHCP leases, or 'agent' to query the guest OS via an
agent. If unspecified, 'lease' is the default.
domifstat domain interface-device
Get network interface stats for a running domain.
domif-setlink domain interface-device state [--config]
Modify link state of the domain's virtual interface. Possible values for state are
"up" and "down". If --config is specified, only the persistent configuration of the
domain is modified, for compatibility purposes, --persistent is alias of --config.
interface-device can be the interface's target name or the MAC address.
domif-getlink domain interface-device [--config]
Query link state of the domain's virtual interface. If --config is specified, query
the persistent configuration, for compatibility purposes, --persistent is alias of
--config.
interface-device can be the interface's target name or the MAC address.
domiftune domain interface-device [[--config] [--live] | [--current]] [--inbound
average,peak,burst,floor] [--outbound average,peak,burst]
Set or query the domain's network interface's bandwidth parameters. interface-device
can be the interface's target name (<target dev='name'/>), or the MAC address.
If no --inbound or --outbound is specified, this command will query and show the
bandwidth settings. Otherwise, it will set the inbound or outbound bandwidth.
average,peak,burst,floor is the same as in command attach-interface. Values for
average, peak and floor are expressed in kilobytes per second, while burst is
expressed in kilobytes in a single burst at peak speed as described in the Network XML
documentation at <http://libvirt.org/formatnetwork.html#elementQoS>.
To clear inbound or outbound settings, use --inbound or --outbound respectfully with
average value of zero.
If --live is specified, affect a running guest. If --config is specified, affect the
next boot of a persistent guest. If --current is specified, affect the current guest
state. Both --live and --config flags may be given, but --current is exclusive. If no
flag is specified, behavior is different depending on hypervisor.
dommemstat domain [--period seconds] [[--config] [--live] | [--current]]
Get memory stats for a running domain.
Depending on the hypervisor a variety of statistics can be returned
For QEMU/KVM with a memory balloon, setting the optional --period to a value larger
than 0 in seconds will allow the balloon driver to return additional statistics which
will be displayed by subsequent dommemstat commands. Setting the --period to 0 will
stop the balloon driver collection, but does not clear the statistics in the balloon
driver. Requires at least QEMU/KVM 1.5 to be running on the host.
The --live, --config, and --current flags are only valid when using the --period
option in order to set the collection period for the balloon driver. If --live is
specified, only the running guest collection period is affected. If --config is
specified, affect the next boot of a persistent guest. If --current is specified,
affect the current guest state.
Both --live and --config flags may be given, but --current is exclusive. If no flag is
specified, behavior is different depending on the guest state.
domblkerror domain
Show errors on block devices. This command usually comes handy when domstate command
says that a domain was paused due to I/O error. The domblkerror command lists all
block devices in error state and the error seen on each of them.
domblkinfo domain block-device
Get block device size info for a domain. A block-device corresponds to a unique
target name (<target dev='name'/>) or source file (<source file='name'/>) for one of
the disk devices attached to domain (see also domblklist for listing these names).
domblklist domain [--inactive] [--details]
Print a table showing the brief information of all block devices associated with
domain. If --inactive is specified, query the block devices that will be used on the
next boot, rather than those currently in use by a running domain. If --details is
specified, disk type and device value will also be printed. Other contexts that
require a block device name (such as domblkinfo or snapshot-create for disk snapshots)
will accept either target or unique source names printed by this command.
domstats [--raw] [--enforce] [--backing] [--state] [--cpu-total] [--balloon] [--vcpu]
[--interface] [--block] [[--list-active] [--list-inactive] [--list-persistent]
[--list-transient] [--list-running] [--list-paused] [--list-shutoff] [--list-other]] |
[domain ...]
Get statistics for multiple or all domains. Without any argument this command prints
all available statistics for all domains.
The list of domains to gather stats for can be either limited by listing the domains
as a space separated list, or by specifying one of the filtering flags --list-*. (The
approaches can't be combined.)
By default some of the returned fields may be converted to more human friendly values
by a set of pretty-printers. To suppress this behavior use the --raw flag.
The individual statistics groups are selectable via specific flags. By default all
supported statistics groups are returned. Supported statistics groups flags are:
--state, --cpu-total, --balloon, --vcpu, --interface, --block.
When selecting the --state group the following fields are returned: "state.state" -
state of the VM, returned as number from virDomainState enum, "state.reason" - reason
for entering given state, returned as int from virDomain*Reason enum corresponding to
given state.
--cpu-total returns: "cpu.time" - total cpu time spent for this domain in nanoseconds,
"cpu.user" - user cpu time spent in nanoseconds, "cpu.system" - system cpu time spent
in nanoseconds
--balloon returns: "balloon.current" - the memory in kiB currently used,
"balloon.maximum" - the maximum memory in kiB allowed
--vcpu returns: "vcpu.current" - current number of online virtual CPUs, "vcpu.maximum"
- maximum number of online virtual CPUs, "vcpu.<num>.state" - state of the virtual CPU
<num>, as number from virVcpuState enum, "vcpu.<num>.time" - virtual cpu time spent by
virtual CPU <num>
--interface returns: "net.count" - number of network interfaces on this domain,
"net.<num>.name" - name of the interface <num>, "net.<num>.rx.bytes" - number of bytes
received, "net.<num>.rx.pkts" - number of packets received, "net.<num>.rx.errs" -
number of receive errors, "net.<num>.rx.drop" - number of receive packets dropped,
"net.<num>.tx.bytes" - number of bytes transmitted, "net.<num>.tx.pkts" - number of
packets transmitted, "net.<num>.tx.errs" - number of transmission errors,
"net.<num>.tx.drop" - number of transmit packets dropped
--block returns information about disks associated with each domain. Using the
--backing flag extends this information to cover all resources in the backing chain,
rather than the default of limiting information to the active layer for each guest
disk. Information listed includes: "block.count" - number of block devices being
listed, "block.<num>.name" - name of the target of the block device <num> (the same
name for multiple entries if --backing is present), "block.<num>.backingIndex" - when
--backing is present, matches up with the <backingStore> index listed in domain XML
for backing files, "block.<num>.path" - file source of block device <num>, if it is a
local file or block device, "block.<num>.rd.reqs" - number of read requests,
"block.<num>.rd.bytes" - number of read bytes, "block.<num>.rd.times" - total time
(ns) spent on reads, "block.<num>.wr.reqs" - number of write requests,
"block.<num>.wr.bytes" - number of written bytes, "block.<num>.wr.times" - total time
(ns) spent on writes, "block.<num>.fl.reqs" - total flush requests,
"block.<num>.fl.times" - total time (ns) spent on cache flushing, "block.<num>.errors"
- Xen only: the 'oo_req' value, "block.<num>.allocation" - offset of highest written
sector in bytes, "block.<num>.capacity" - logical size of source file in bytes,
"block.<num>.physical" - physical size of source file in bytes
Selecting a specific statistics groups doesn't guarantee that the daemon supports the
selected group of stats. Flag --enforce forces the command to fail if the daemon
doesn't support the selected group.
domiflist domain [--inactive]
Print a table showing the brief information of all virtual interfaces associated with
domain. If --inactive is specified, query the virtual interfaces that will be used on
the next boot, rather than those currently in use by a running domain. Other contexts
that require a MAC address of virtual interface (such as detach-interface or domif-
setlink) will accept the MAC address printed by this command.
blockcommit domain path [bandwidth] [base] [--shallow] [top] [--delete] [--keep-relative]
[--wait [--async] [--verbose]] [--timeout seconds] [--active] [{--pivot | --keep-overlay}]
Reduce the length of a backing image chain, by committing changes at the top of the
chain (snapshot or delta files) into backing images. By default, this command
attempts to flatten the entire chain. If base and/or top are specified as files
within the backing chain, then the operation is constrained to committing just that
portion of the chain; --shallow can be used instead of base to specify the immediate
backing file of the resulting top image to be committed. The files being committed
are rendered invalid, possibly as soon as the operation starts; using the --delete
flag will attempt to remove these invalidated files at the successful completion of
the commit operation. When the --keep-relative flag is used, the backing file paths
will be kept relative.
When top is omitted or specified as the active image, it is also possible to specify
--active to trigger a two-phase active commit. In the first phase, top is copied into
base and the job can only be canceled, with top still containing data not yet in base.
In the second phase, top and base remain identical until a call to blockjob with the
--abort flag (keeping top as the active image that tracks changes from that point in
time) or the --pivot flag (making base the new active image and invalidating top).
By default, this command returns as soon as possible, and data for the entire disk is
committed in the background; the progress of the operation can be checked with
blockjob. However, if --wait is specified, then this command will block until the
operation completes (or for --active, enters the second phase), or until the operation
is canceled because the optional timeout in seconds elapses or SIGINT is sent (usually
with "Ctrl-C"). Using --verbose along with --wait will produce periodic status
updates. If job cancellation is triggered, --async will return control to the user as
fast as possible, otherwise the command may continue to block a little while longer
until the job is done cleaning up. Using --pivot is shorthand for combining --active
--wait with an automatic blockjob --pivot; and using --keep-overlay is shorthand for
combining --active --wait with an automatic blockjob --abort.
path specifies fully-qualified path of the disk; it corresponds to a unique target
name (<target dev='name'/>) or source file (<source file='name'/>) for one of the disk
devices attached to domain (see also domblklist for listing these names). bandwidth
specifies copying bandwidth limit in MiB/s, although for qemu, it may be non-zero only
for an online domain. Specifying a negative value is interpreted as an unsigned long
long value or essentially unlimited. The hypervisor can choose whether to reject the
value or convert it to the maximum value allowed.
blockcopy domain path { dest [format] [--blockdev] | --xml file } [--shallow]
[--reuse-external] [bandwidth] [--wait [--async] [--verbose]] [{--pivot | --finish}]
[--timeout seconds] [granularity] [buf-size]
Copy a disk backing image chain to a destination. Either dest as the destination file
name, or --xml with the name of an XML file containing a top-level <disk> element
describing the destination, must be present. Additionally, if dest is given, format
should be specified to declare the format of the destination (if format is omitted,
then libvirt will reuse the format of the source, or with --reuse-external will be
forced to probe the destination format, which could be a potential security hole).
The command supports --raw as a boolean flag synonym for --format=raw. When using
dest, the destination is treated as a regular file unless --blockdev is used to signal
that it is a block device. By default, this command flattens the entire chain; but if
--shallow is specified, the copy shares the backing chain.
If --reuse-external is specified, then the destination must exist and have sufficient
space to hold the copy. If --shallow is used in conjunction with --reuse-external then
the pre-created image must have guest visible contents identical to guest visible
contents of the backing file of the original image. This may be used to modify the
backing file names on the destination.
By default, the copy job runs in the background, and consists of two phases.
Initially, the job must copy all data from the source, and during this phase, the job
can only be canceled to revert back to the source disk, with no guarantees about the
destination. After this phase completes, both the source and the destination remain
mirrored until a call to blockjob with the --abort and --pivot flags pivots over to
the copy, or a call without --pivot leaves the destination as a faithful copy of that
point in time. However, if --wait is specified, then this command will block until
the mirroring phase begins, or cancel the operation if the optional timeout in seconds
elapses or SIGINT is sent (usually with "Ctrl-C"). Using --verbose along with --wait
will produce periodic status updates. Using --pivot (similar to blockjob --pivot) or
--finish (similar to blockjob --abort) implies --wait, and will additionally end the
job cleanly rather than leaving things in the mirroring phase. If job cancellation is
triggered by timeout or by --finish, --async will return control to the user as fast
as possible, otherwise the command may continue to block a little while longer until
the job has actually cancelled.
path specifies fully-qualified path of the disk. bandwidth specifies copying
bandwidth limit in MiB/s. Specifying a negative value is interpreted as an unsigned
long long value that might be essentially unlimited, but more likely would overflow;
it is safer to use 0 for that purpose. Specifying granularity allows fine-tuning of
the granularity that will be copied when a dirty region is detected; larger values
trigger less I/O overhead but may end up copying more data overall (the default value
is usually correct); hypervisors may restrict this to be a power of two or fall within
a certain range. Specifying buf-size will control how much data can be simultaneously
in-flight during the copy; larger values use more memory but may allow faster
completion (the default value is usually correct).
blockpull domain path [bandwidth] [base] [--wait [--verbose] [--timeout seconds]
[--async]] [--keep-relative]
Populate a disk from its backing image chain. By default, this command flattens the
entire chain; but if base is specified, containing the name of one of the backing
files in the chain, then that file becomes the new backing file and only the
intermediate portion of the chain is pulled. Once all requested data from the backing
image chain has been pulled, the disk no longer depends on that portion of the backing
chain.
By default, this command returns as soon as possible, and data for the entire disk is
pulled in the background; the progress of the operation can be checked with blockjob.
However, if --wait is specified, then this command will block until the operation
completes, or cancel the operation if the optional timeout in seconds elapses or
SIGINT is sent (usually with "Ctrl-C"). Using --verbose along with --wait will
produce periodic status updates. If job cancellation is triggered, --async will
return control to the user as fast as possible, otherwise the command may continue to
block a little while longer until the job is done cleaning up.
Using the --keep-relative flag will keep the backing chain names relative.
path specifies fully-qualified path of the disk; it corresponds to a unique target
name (<target dev='name'/>) or source file (<source file='name'/>) for one of the disk
devices attached to domain (see also domblklist for listing these names). bandwidth
specifies copying bandwidth limit in MiB/s. Specifying a negative value is interpreted
as an unsigned long long value or essentially unlimited. The hypervisor can choose
whether to reject the value or convert it to the maximum value allowed.
blkdeviotune domain device [[--config] [--live] | [--current]] [[total-bytes-sec] | [read-
bytes-sec] [write-bytes-sec]] [[total-iops-sec] | [read-iops-sec] [write-iops-sec]]
[[total-bytes-sec-max] | [read-bytes-sec-max] [write-bytes-sec-max]] [[total-iops-sec-max]
| [read-iops-sec-max] [write-iops-sec-max]] [size-iops-sec]
Set or query the block disk io parameters for a block device of domain. device
specifies a unique target name (<target dev='name'/>) or source file (<source
file='name'/>) for one of the disk devices attached to domain (see also domblklist for
listing these names).
If no limit is specified, it will query current I/O limits setting. Otherwise, alter
the limits with these flags: --total-bytes-sec specifies total throughput limit in
bytes per second. --read-bytes-sec specifies read throughput limit in bytes per
second. --write-bytes-sec specifies write throughput limit in bytes per second.
--total-iops-sec specifies total I/O operations limit per second. --read-iops-sec
specifies read I/O operations limit per second. --write-iops-sec specifies write I/O
operations limit per second. --total-bytes-sec-max specifies maximum total throughput
limit in bytes per second. --read-bytes-sec-max specifies maximum read throughput
limit in bytes per second. --write-bytes-sec-max specifies maximum write throughput
limit in bytes per second. --total-iops-sec-max specifies maximum total I/O
operations limit per second. --read-iops-sec-max specifies maximum read I/O
operations limit per second. --write-iops-sec-max specifies maximum write I/O
operations limit per second. --size-iops-sec specifies size I/O operations limit per
second.
Older versions of virsh only accepted these options with underscore instead of dash,
as in --total_bytes_sec.
Bytes and iops values are independent, but setting only one value (such as
--read-bytes-sec) resets the other two in that category to unlimited. An explicit 0
also clears any limit. A non-zero value for a given total cannot be mixed with non-
zero values for read or write.
If --live is specified, affect a running guest. If --config is specified, affect the
next boot of a persistent guest. If --current is specified, affect the current guest
state. When setting the disk io parameters both --live and --config flags may be
given, but --current is exclusive. For querying only one of --live, --config or
--current can be specified. If no flag is specified, behavior is different depending
on hypervisor.
blockjob domain path { [--abort] [--async] [--pivot] | [--info] [--raw] [--bytes] |
[bandwidth] }
Manage active block operations. There are three mutually-exclusive modes: --info,
bandwidth, and --abort. --async and --pivot imply abort mode; --raw implies info
mode; and if no mode was given, --info mode is assumed.
path specifies fully-qualified path of the disk; it corresponds to a unique target
name (<target dev='name'/>) or source file (<source file='name'/>) for one of the disk
devices attached to domain (see also domblklist for listing these names).
In --abort mode, the active job on the specified disk will be aborted. If --async is
also specified, this command will return immediately, rather than waiting for the
cancellation to complete. If --pivot is specified, this requests that an active copy
or active commit job be pivoted over to the new image.
In --info mode, the active job information on the specified disk will be printed. By
default, the output is a single human-readable summary line; this format may change in
future versions. Adding --raw lists each field of the struct, in a stable format. If
the --bytes flag is set, then the command errors out if the server could not supply
bytes/s resolution; when omitting the flag, raw output is listed in MiB/s and human-
readable output automatically selects the best resolution supported by the server.
bandwidth can be used to set bandwidth limit for the active job. Specifying a
negative value is interpreted as an unsigned long long value or essentially unlimited.
The hypervisor can choose whether to reject the value or convert it to the maximum
value allowed.
blockresize domain path size
Resize a block device of domain while the domain is running, path specifies the
absolute path of the block device; it corresponds to a unique target name (<target
dev='name'/>) or source file (<source file='name'/>) for one of the disk devices
attached to domain (see also domblklist for listing these names).
size is a scaled integer (see NOTES above) which defaults to KiB (blocks of 1024
bytes) if there is no suffix. You must use a suffix of "B" to get bytes (note that
for historical reasons, this differs from vol-resize which defaults to bytes without a
suffix).
domdisplay domain [--include-password] [[--type] type]
Output a URI which can be used to connect to the graphical display of the domain via
VNC, SPICE or RDP. The particular graphical display type can be selected using the
type parameter (e.g. "vnc", "spice", "rdp"). If --include-password is specified, the
SPICE channel password will be included in the URI.
domfsinfo domain
Show a list of mounted filesystems within the running domain. The list contains
mountpoints, names of a mounted device in the guest, filesystem types, and unique
target names used in the domain XML (<target dev='name'/>).
Note that this command requires a guest agent configured and running in the domain's
guest OS.
domfsfreeze domain [[--mountpoint] mountpoint...]
Freeze mounted filesystems within a running domain to prepare for consistent
snapshots.
The --mountpoint option takes a parameter mountpoint, which is a mount point path of
the filesystem to be frozen. This option can occur multiple times. If this is not
specified, every mounted filesystem is frozen.
Note: snapshot-create command has a --quiesce option to freeze and thaw the
filesystems automatically to keep snapshots consistent. domfsfreeze command is only
needed when a user wants to utilize the native snapshot features of storage devices
not supported by libvirt.
domfsthaw domain [[--mountpoint] mountpoint...]
Thaw mounted filesystems within a running domain, which have been frozen by
domfsfreeze command.
The --mountpoint option takes a parameter mountpoint, which is a mount point path of
the filesystem to be thawed. This option can occur multiple times. If this is not
specified, every mounted filesystem is thawed.
domfstrim domain [--minimum bytes] [--mountpoint mountPoint]
Issue a fstrim command on all mounted filesystems within a running domain. It discards
blocks which are not in use by the filesystem. If --minimum bytes is specified, it
tells guest kernel length of contiguous free range. Smaller than this may be ignored
(this is a hint and the guest may not respect it). By increasing this value, the
fstrim operation will complete more quickly for filesystems with badly fragmented free
space, although not all blocks will be discarded. The default value is zero, meaning
"discard every free block". Moreover, a if user wants to trim only one mount point, it
can be specified via optional --mountpoint parameter.
domhostname domain
Returns the hostname of a domain, if the hypervisor makes it available.
dominfo domain
Returns basic information about the domain.
domuuid domain-name-or-id
Convert a domain name or id to domain UUID
domid domain-name-or-uuid
Convert a domain name (or UUID) to a domain id
domjobabort domain
Abort the currently running domain job.
domjobinfo domain [--completed]
Returns information about jobs running on a domain. --completed tells virsh to return
information about a recently finished job. Statistics of a completed job are
automatically destroyed once read or when libvirtd is restarted. Note that time
information returned for completed migrations may be completely irrelevant unless both
source and destination hosts have synchronized time (i.e., NTP daemon is running on
both of them).
domname domain-id-or-uuid
Convert a domain Id (or UUID) to domain name
domrename domain new-name
Rename a domain. This command changes current domain name to the new name specified in
the second argument.
Note: Domain must be inactive and without snapshots.
domstate domain [--reason]
Returns state about a domain. --reason tells virsh to also print reason for the
state.
domcontrol domain
Returns state of an interface to VMM used to control a domain. For states other than
"ok" or "error" the command also prints number of seconds elapsed since the control
interface entered its current state.
domtime domain { [--now] [--pretty] [--sync] [--time time] }
Gets or sets the domain's system time. When run without any arguments (but domain),
the current domain's system time is printed out. The --pretty modifier can be used to
print the time in more human readable form.
When --time time is specified, the domain's time is not gotten but set instead. The
--now modifier acts like if it was an alias for --time $now, which means it sets the
time that is currently on the host virsh is running at. In both cases (setting and
getting), time is in seconds relative to Epoch of 1970-01-01 in UTC. The --sync
modifies the set behavior a bit: The time passed is ignored, but the time to set is
read from domain's RTC instead. Please note, that some hypervisors may require a guest
agent to be configured in order to get or set the guest time.
domxml-from-native format config
Convert the file config in the native guest configuration format named by format to a
domain XML format. For QEMU/KVM hypervisor, the format argument must be qemu-argv. For
Xen hypervisor, the format argument may be xen-xm, xen-xl, or xen-sxpr. For LXC
hypervisor, the format argument must be lxc-tools.
domxml-to-native format xml
Convert the file xml in domain XML format to the native guest configuration format
named by format. For QEMU/KVM hypervisor, the format argument must be qemu-argv. For
Xen hypervisor, the format argument may be xen-xm, xen-xl, or xen-sxpr. For LXC
hypervisor, the format argument must be lxc-tools.
dump domain corefilepath [--bypass-cache] { [--live] | [--crash] | [--reset] } [--verbose]
[--memory-only] [--format string]
Dumps the core of a domain to a file for analysis. If --live is specified, the domain
continues to run until the core dump is complete, rather than pausing up front. If
--crash is specified, the domain is halted with a crashed status, rather than merely
left in a paused state. If --reset is specified, the domain is reset after successful
dump. Note, these three switches are mutually exclusive. If --bypass-cache is
specified, the save will avoid the file system cache, although this may slow down the
operation. If --memory-only is specified, the file is elf file, and will only include
domain's memory and cpu common register value. It is very useful if the domain uses
host devices directly. --format string is used to specify the format of 'memory-only'
dump, and string can be one of them: elf, kdump-zlib(kdump-compressed format with
zlib-compressed), kdump-lzo(kdump-compressed format with lzo-compressed),
kdump-snappy(kdump-compressed format with snappy-compressed).
The progress may be monitored using domjobinfo virsh command and canceled with
domjobabort command (sent by another virsh instance). Another option is to send SIGINT
(usually with "Ctrl-C") to the virsh process running dump command. --verbose displays
the progress of dump.
NOTE: Some hypervisors may require the user to manually ensure proper permissions on
file and path specified by argument corefilepath.
dumpxml domain [--inactive] [--security-info] [--update-cpu] [--migratable]
Output the domain information as an XML dump to stdout, this format can be used by the
create command. Additional options affecting the XML dump may be used. --inactive
tells virsh to dump domain configuration that will be used on next start of the domain
as opposed to the current domain configuration. Using --security-info will also
include security sensitive information in the XML dump. --update-cpu updates domain
CPU requirements according to host CPU. With --migratable one can request an XML that
is suitable for migrations, i.e., compatible with older libvirt releases and possibly
amended with internal run-time options. This option may automatically enable other
options (--update-cpu, --security-info, ...) as necessary.
edit domain
Edit the XML configuration file for a domain, which will affect the next boot of the
guest.
This is equivalent to:
virsh dumpxml --inactive --security-info domain > domain.xml
vi domain.xml (or make changes with your other text editor)
virsh define domain.xml
except that it does some error checking.
The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and
defaults to "vi".
event {[domain] { event | --all } [--loop] [--timeout seconds] [--timestamp] | --list}
Wait for a class of domain events to occur, and print appropriate details of events as
they happen. The events can optionally be filtered by domain. Using --list as the
only argument will provide a list of possible event values known by this client,
although the connection might not allow registering for all these events. It is also
possible to use --all instead of event to register for all possible event types at
once.
By default, this command is one-shot, and returns success once an event occurs; you
can send SIGINT (usually via "Ctrl-C") to quit immediately. If --timeout is
specified, the command gives up waiting for events after seconds have elapsed. With
--loop, the command prints all events until a timeout or interrupt key.
When --timestamp is used, a human-readable timestamp will be printed before the event.
iothreadinfo domain [[--live] [--config] | [--current]]
Display basic domain IOThreads information including the IOThread ID and the CPU
Affinity for each IOThread.
If --live is specified, get the IOThreads data from the running guest. If the guest is
not running, an error is returned. If --config is specified, get the IOThreads data
from the next boot of a persistent guest. If --current is specified or --live and
--config are not specified, then get the IOThread data based on the current guest
state.
iothreadpin domain iothread cpulist [[--live] [--config] | [--current]]
Change the pinning of a domain IOThread to host physical CPUs. In order to retrieve a
list of all IOThreads, use iothreadinfo. To pin an iothread specify the cpulist
desired for the IOThread ID as listed in the iothreadinfo output.
cpulist is a list of physical CPU numbers. Its syntax is a comma separated list and a
special markup using '-' and '^' (ex. '0-4', '0-3,^2') can also be allowed. The '-'
denotes the range and the '^' denotes exclusive. If you want to reset iothreadpin
setting, that is, to pin an iothread to all physical cpus, simply specify 'r' as a
cpulist.
If --live is specified, affect a running guest. If the guest is not running, an error
is returned. If --config is specified, affect the next boot of a persistent guest.
If --current is specified or --live and --config are not specified, affect the current
guest state. Both --live and --config flags may be given if cpulist is present, but
--current is exclusive. If no flag is specified, behavior is different depending on
hypervisor.
Note: The expression is sequentially evaluated, so "0-15,^8" is identical to
"9-14,0-7,15" but not identical to "^8,0-15".
iothreadadd domain iothread_id [[--config] [--live] | [--current]]
Add a new IOThread to the domain using the specified iothread_id. If the iothread_id
already exists, the command will fail. The iothread_id must be greater than zero.
If --live is specified, affect a running guest. If the guest is not running an error
is returned. If --config is specified, affect the next boot of a persistent guest.
If --current is specified or --live and --config are not specified, affect the current
guest state.
iothreaddel domain iothread_id [[--config] [--live] | [--current]]
Delete an IOThread from the domain using the specified iothread_id. If an IOThread is
currently assigned to a disk resource such as via the attach-disk command, then the
attempt to remove the IOThread will fail. If the iothread_id does not exist an error
will occur.
If --live is specified, affect a running guest. If the guest is not running an error
is returned. If --config is specified, affect the next boot of a persistent guest.
If --current is specified or --live and --config are not specified, affect the current
guest state.
managedsave domain [--bypass-cache] [{--running | --paused}] [--verbose]
Save and destroy (stop) a running domain, so it can be restarted from the same state
at a later time. When the virsh start command is next run for the domain, it will
automatically be started from this saved state. If --bypass-cache is specified, the
save will avoid the file system cache, although this may slow down the operation.
The progress may be monitored using domjobinfo virsh command and canceled with
domjobabort command (sent by another virsh instance). Another option is to send SIGINT
(usually with "Ctrl-C") to the virsh process running managedsave command. --verbose
displays the progress of save.
Normally, starting a managed save will decide between running or paused based on the
state the domain was in when the save was done; passing either the --running or
--paused flag will allow overriding which state the start should use.
The dominfo command can be used to query whether a domain currently has any managed
save image.
managedsave-remove domain
Remove the managedsave state file for a domain, if it exists. This ensures the domain
will do a full boot the next time it is started.
maxvcpus [type]
Provide the maximum number of virtual CPUs supported for a guest VM on this
connection. If provided, the type parameter must be a valid type attribute for the
<domain> element of XML.
cpu-stats domain [--total] [start] [count]
Provide cpu statistics information of a domain. The domain should be running. Default
it shows stats for all CPUs, and a total. Use --total for only the total stats, start
for only the per-cpu stats of the CPUs from start, count for only count CPUs' stats.
metadata domain [[--live] [--config] | [--current]] [--edit] [uri] [key] [set] [--remove]
Show or modify custom XML metadata of a domain. The metadata is a user defined XML
that allows to store arbitrary XML data in the domain definition. Multiple separate
custom metadata pieces can be stored in the domain XML. The pieces are identified by
a private XML namespace provided via the uri argument. (See also desc that works with
textual metadata of a domain.)
Flags --live or --config select whether this command works on live or persistent
definitions of the domain. If both --live and --config are specified, the --config
option takes precedence on getting the current description and both live configuration
and config are updated while setting the description. --current is exclusive and
implied if none of these was specified.
Flag --remove specifies that the metadata element specified by the uri argument should
be removed rather than updated.
Flag --edit specifies that an editor with the metadata identified by the uri argument
should be opened and the contents saved back afterwards. Otherwise the new contents
can be provided via the set argument.
When setting metadata via --edit or set the key argument must be specified and is used
to prefix the custom elements to bind them to the private namespace.
If neither of --edit and set are specified the XML metadata corresponding to the uri
namespace is displayed instead of being modified.
migrate [--live] [--offline] [--direct] [--p2p [--tunnelled]] [--persistent]
[--undefinesource] [--suspend] [--copy-storage-all] [--copy-storage-inc]
[--change-protection] [--unsafe] [--verbose] [--compressed] [--abort-on-error]
[--auto-converge] domain desturi [migrateuri] [graphicsuri] [listen-address] [dname]
[--timeout seconds] [--xml file] [--migrate-disks disk-list]
Migrate domain to another host. Add --live for live migration; <--p2p> for
peer-2-peer migration; --direct for direct migration; or --tunnelled for tunnelled
migration. --offline migrates domain definition without starting the domain on
destination and without stopping it on source host. Offline migration may be used
with inactive domains and it must be used with --persistent option. --persistent
leaves the domain persistent on destination host, --undefinesource undefines the
domain on the source host, and --suspend leaves the domain paused on the destination
host. --copy-storage-all indicates migration with non-shared storage with full disk
copy, --copy-storage-inc indicates migration with non-shared storage with incremental
copy (same base image shared between source and destination). In both cases the disk
images have to exist on destination host, the --copy-storage-... options only tell
libvirt to transfer data from the images on source host to the images found at the
same place on the destination host. By default only non-shared non-readonly images are
transferred. Use --migrate-disks to explicitly specify a list of disk targets to
transfer via the comma separated disk-list argument. --change-protection enforces that
no incompatible configuration changes will be made to the domain while the migration
is underway; this flag is implicitly enabled when supported by the hypervisor, but can
be explicitly used to reject the migration if the hypervisor lacks change protection
support. --verbose displays the progress of migration. --compressed activates
compression of memory pages that have to be transferred repeatedly during live
migration. --abort-on-error cancels the migration if a soft error (for example I/O
error) happens during the migration. --auto-converge forces convergence during live
migration.
Note: Individual hypervisors usually do not support all possible types of migration.
For example, QEMU does not support direct migration.
In some cases libvirt may refuse to migrate the domain because doing so may lead to
potential problems such as data corruption, and thus the migration is considered
unsafe. For QEMU domain, this may happen if the domain uses disks without explicitly
setting cache mode to "none". Migrating such domains is unsafe unless the disk images
are stored on coherent clustered filesystem, such as GFS2 or GPFS. If you are sure the
migration is safe or you just do not care, use --unsafe to force the migration.
dname is used for renaming the domain to new name during migration, which also usually
can be omitted. Likewise, --xml file is usually omitted, but can be used to supply an
alternative XML file for use on the destination to supply a larger set of changes to
any host-specific portions of the domain XML, such as accounting for naming
differences between source and destination in accessing underlying storage.
--timeout seconds forces guest to suspend when live migration exceeds that many
seconds, and then the migration will complete offline. It can only be used with
--live.
Running migration can be canceled by interrupting virsh (usually using "Ctrl-C") or by
domjobabort command sent from another virsh instance.
The desturi and migrateuri parameters can be used to control which destination the
migration uses. desturi is important for managed migration, but unused for direct
migration; migrateuri is required for direct migration, but can usually be
automatically determined for managed migration.
Note: The desturi parameter for normal migration and peer2peer migration has different
semantics:
· normal migration: the desturi is an address of the target host as seen from the
client machine.
· peer2peer migration: the desturi is an address of the target host as seen from the
source machine.
When migrateuri is not specified, libvirt will automatically determine the hypervisor
specific URI. Some hypervisors, including QEMU, have an optional "migration_host"
configuration parameter (useful when the host has multiple network interfaces). If
this is unspecified, libvirt determines a name by looking up the target host's
configured hostname.
There are a few scenarios where specifying migrateuri may help:
· The configured hostname is incorrect, or DNS is broken. If a host has a hostname
which will not resolve to match one of its public IP addresses, then libvirt will
generate an incorrect URI. In this case migrateuri should be explicitly
specified, using an IP address, or a correct hostname.
· The host has multiple network interfaces. If a host has multiple network
interfaces, it might be desirable for the migration data stream to be sent over a
specific interface for either security or performance reasons. In this case
migrateuri should be explicitly specified, using an IP address associated with the
network to be used.
· The firewall restricts what ports are available. When libvirt generates a
migration URI, it will pick a port number using hypervisor specific rules. Some
hypervisors only require a single port to be open in the firewalls, while others
require a whole range of port numbers. In the latter case migrateuri might be
specified to choose a specific port number outside the default range in order to
comply with local firewall policies.
See <http://libvirt.org/migration.html#uris> for more details on migration URIs.
Optional graphicsuri overrides connection parameters used for automatically
reconnecting a graphical clients at the end of migration. If omitted, libvirt will
compute the parameters based on target host IP address. In case the client does not
have a direct access to the network virtualization hosts are connected to and needs to
connect through a proxy, graphicsuri may be used to specify the address the client
should connect to. The URI is formed as follows:
protocol://hostname[:port]/[?parameters]
where protocol is either "spice" or "vnc" and parameters is a list of protocol
specific parameters separated by '&'. Currently recognized parameters are "tlsPort"
and "tlsSubject". For example,
spice://target.host.com:1234/?tlsPort=4567
Optional listen-address sets the listen address that hypervisor on the destination
side should bind to for incoming migration. Both IPv4 and IPv6 addresses are accepted
as well as hostnames (the resolving is done on destination). Some hypervisors do not
support this feature and will return an error if this parameter is used.
migrate-setmaxdowntime domain downtime
Set maximum tolerable downtime for a domain which is being live-migrated to another
host. The downtime is a number of milliseconds the guest is allowed to be down at the
end of live migration.
migrate-compcache domain [--size bytes]
Sets and/or gets size of the cache (in bytes) used for compressing repeatedly
transferred memory pages during live migration. When called without size, the command
just prints current size of the compression cache. When size is specified, the
hypervisor is asked to change compression cache to size bytes and then the current
size is printed (the result may differ from the requested size due to rounding done by
the hypervisor). The size option is supposed to be used while the domain is being
live-migrated as a reaction to migration progress and increasing number of compression
cache misses obtained from domjobinfo.
migrate-setspeed domain bandwidth
Set the maximum migration bandwidth (in MiB/s) for a domain which is being migrated to
another host. bandwidth is interpreted as an unsigned long long value. Specifying a
negative value results in an essentially unlimited value being provided to the
hypervisor. The hypervisor can choose whether to reject the value or convert it to the
maximum value allowed.
migrate-getspeed domain
Get the maximum migration bandwidth (in MiB/s) for a domain.
numatune domain [--mode mode] [--nodeset nodeset] [[--config] [--live] | [--current]]
Set or get a domain's numa parameters, corresponding to the <numatune> element of
domain XML. Without flags, the current settings are displayed.
mode can be one of `strict', `interleave' and `preferred' or any valid number from the
virDomainNumatuneMemMode enum in case the daemon supports it. For a running domain,
the mode can't be changed, and the nodeset can be changed only if the domain was
started with a mode of `strict'.
nodeset is a list of numa nodes used by the host for running the domain. Its syntax
is a comma separated list, with '-' for ranges and '^' for excluding a node.
If --live is specified, set scheduler information of a running guest. If --config is
specified, affect the next boot of a persistent guest. If --current is specified,
affect the current guest state.
reboot domain [--mode MODE-LIST]
Reboot a domain. This acts just as if the domain had the reboot command run from the
console. The command returns as soon as it has executed the reboot action, which may
be significantly before the domain actually reboots.
The exact behavior of a domain when it reboots is set by the on_reboot parameter in
the domain's XML definition.
By default the hypervisor will try to pick a suitable shutdown method. To specify an
alternative method, the --mode parameter can specify a comma separated list which
includes "acpi", "agent", "initctl", "signal" and "paravirt". The order in which
drivers will try each mode is undefined, and not related to the order specified to
virsh. For strict control over ordering, use a single mode at a time and repeat the
command.
reset domain
Reset a domain immediately without any guest shutdown. reset emulates the power reset
button on a machine, where all guest hardware sees the RST line set and reinitializes
internal state.
Note: Reset without any guest OS shutdown risks data loss.
restore state-file [--bypass-cache] [--xml file] [{--running | --paused}]
Restores a domain from a virsh save state file. See save for more info.
If --bypass-cache is specified, the restore will avoid the file system cache, although
this may slow down the operation.
--xml file is usually omitted, but can be used to supply an alternative XML file for
use on the restored guest with changes only in the host-specific portions of the
domain XML. For example, it can be used to account for file naming differences in
underlying storage due to disk snapshots taken after the guest was saved.
Normally, restoring a saved image will use the state recorded in the save image to
decide between running or paused; passing either the --running or --paused flag will
allow overriding which state the domain should be started in.
Note: To avoid corrupting file system contents within the domain, you should not reuse
the saved state file for a second restore unless you have also reverted all storage
volumes back to the same contents as when the state file was created.
save domain state-file [--bypass-cache] [--xml file] [{--running | --paused}] [--verbose]
Saves a running domain (RAM, but not disk state) to a state file so that it can be
restored later. Once saved, the domain will no longer be running on the system, thus
the memory allocated for the domain will be free for other domains to use. virsh
restore restores from this state file. If --bypass-cache is specified, the save will
avoid the file system cache, although this may slow down the operation.
The progress may be monitored using domjobinfo virsh command and canceled with
domjobabort command (sent by another virsh instance). Another option is to send SIGINT
(usually with "Ctrl-C") to the virsh process running save command. --verbose displays
the progress of save.
This is roughly equivalent to doing a hibernate on a running computer, with all the
same limitations. Open network connections may be severed upon restore, as TCP
timeouts may have expired.
--xml file is usually omitted, but can be used to supply an alternative XML file for
use on the restored guest with changes only in the host-specific portions of the
domain XML. For example, it can be used to account for file naming differences that
are planned to be made via disk snapshots of underlying storage after the guest is
saved.
Normally, restoring a saved image will decide between running or paused based on the
state the domain was in when the save was done; passing either the --running or
--paused flag will allow overriding which state the restore should use.
Domain saved state files assume that disk images will be unchanged between the
creation and restore point. For a more complete system restore point, where the disk
state is saved alongside the memory state, see the snapshot family of commands.
save-image-define file xml [{--running | --paused}]
Update the domain XML that will be used when file is later used in the restore
command. The xml argument must be a file name containing the alternative XML, with
changes only in the host-specific portions of the domain XML. For example, it can be
used to account for file naming differences resulting from creating disk snapshots of
underlying storage after the guest was saved.
The save image records whether the domain should be restored to a running or paused
state. Normally, this command does not alter the recorded state; passing either the
--running or --paused flag will allow overriding which state the restore should use.
save-image-dumpxml file [--security-info]
Extract the domain XML that was in effect at the time the saved state file file was
created with the save command. Using --security-info will also include security
sensitive information.
save-image-edit file [{--running | --paused}]
Edit the XML configuration associated with a saved state file file created by the save
command.
The save image records whether the domain should be restored to a running or paused
state. Normally, this command does not alter the recorded state; passing either the
--running or --paused flag will allow overriding which state the restore should use.
This is equivalent to:
virsh save-image-dumpxml state-file > state-file.xml
vi state-file.xml (or make changes with your other text editor)
virsh save-image-define state-file state-file-xml
except that it does some error checking.
The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and
defaults to "vi".
schedinfo domain [[--config] [--live] | [--current]] [[--set] parameter=value]...
schedinfo [--weight number] [--cap number] domain
Allows you to show (and set) the domain scheduler parameters. The parameters available
for each hypervisor are:
LXC (posix scheduler) : cpu_shares, vcpu_period, vcpu_quota
QEMU/KVM (posix scheduler): cpu_shares, vcpu_period, vcpu_quota, emulator_period,
emulator_quota
Xen (credit scheduler): weight, cap
ESX (allocation scheduler): reservation, limit, shares
If --live is specified, set scheduler information of a running guest. If --config is
specified, affect the next boot of a persistent guest. If --current is specified,
affect the current guest state.
Note: The cpu_shares parameter has a valid value range of 0-262144; Negative values
are wrapped to positive, and larger values are capped at the maximum. Therefore, -1
is a useful shorthand for 262144. On the Linux kernel, the values 0 and 1 are
automatically converted to a minimal value of 2.
Note: The weight and cap parameters are defined only for the XEN_CREDIT scheduler and
are now DEPRECATED.
Note: The vcpu_period/emulator_period parameters have a valid value range of
1000-1000000 or 0, and the vcpu_quota/emulator_quota parameters have a valid value
range of 1000-18446744073709551 or less than 0. The value 0 for either parameter is
the same as not specifying that parameter.
screenshot domain [imagefilepath] [--screen screenID]
Takes a screenshot of a current domain console and stores it into a file. Optionally,
if hypervisor supports more displays for a domain, screenID allows to specify which
screen will be captured. It is the sequential number of screen. In case of multiple
graphics cards, heads are enumerated before devices, e.g. having two graphics cards,
both with four heads, screen ID 5 addresses the second head on the second card.
send-key domain [--codeset codeset] [--holdtime holdtime] keycode...
Parse the keycode sequence as keystrokes to send to domain. Each keycode can either
be a numeric value or a symbolic name from the corresponding codeset. If --holdtime
is given, each keystroke will be held for that many milliseconds. The default codeset
is linux, but use of the --codeset option allows other codesets to be chosen.
If multiple keycodes are specified, they are all sent simultaneously to the guest, and
they may be received in random order. If you need distinct keypresses, you must use
multiple send-key invocations.
linux
The numeric values are those defined by the Linux generic input event subsystem.
The symbolic names match the corresponding Linux key constant macro names.
xt The numeric values are those defined by the original XT keyboard controller. No
symbolic names are provided
atset1
The numeric values are those defined by the AT keyboard controller, set 1 (aka XT
compatible set). Extended keycoes from atset1 may differ from extended keycodes in
the xt codeset. No symbolic names are provided
atset2
The numeric values are those defined by the AT keyboard controller, set 2. No
symbolic names are provided
atset3
The numeric values are those defined by the AT keyboard controller, set 3 (aka
PS/2 compatible set). No symbolic names are provided
os_x
The numeric values are those defined by the OS-X keyboard input subsystem. The
symbolic names match the corresponding OS-X key constant macro names
xt_kbd
The numeric values are those defined by the Linux KBD device. These are a variant
on the original XT codeset, but often with different encoding for extended
keycodes. No symbolic names are provided.
win32
The numeric values are those defined by the Win32 keyboard input subsystem. The
symbolic names match the corresponding Win32 key constant macro names
usb The numeric values are those defined by the USB HID specification for keyboard
input. No symbolic names are provided
rfb The numeric values are those defined by the RFB extension for sending raw
keycodes. These are a variant on the XT codeset, but extended keycodes have the
low bit of the second byte set, instead of the high bit of the first byte. No
symbolic names are provided.
Examples
# send three strokes 'k', 'e', 'y', using xt codeset. these
# are all pressed simultaneously and may be received by the guest
# in random order
virsh send-key dom --codeset xt 37 18 21
# send one stroke 'right-ctrl+C'
virsh send-key dom KEY_RIGHTCTRL KEY_C
# send a tab, held for 1 second
virsh send-key --holdtime 1000 0xf
send-process-signal domain-id pid signame
Send a signal signame to the process identified by pid running in the virtual domain
domain-id. The pid is a process ID in the virtual domain namespace.
The signame argument may be either an integer signal constant number, or one of the
symbolic names:
"nop", "hup", "int", "quit", "ill",
"trap", "abrt", "bus", "fpe", "kill",
"usr1", "segv", "usr2", "pipe", "alrm",
"term", "stkflt", "chld", "cont", "stop",
"tstp", "ttin", "ttou", "urg", "xcpu",
"xfsz", "vtalrm", "prof", "winch", "poll",
"pwr", "sys", "rt0", "rt1", "rt2", "rt3",
"rt4", "rt5", "rt6", "rt7", "rt8", "rt9",
"rt10", "rt11", "rt12", "rt13", "rt14", "rt15",
"rt16", "rt17", "rt18", "rt19", "rt20", "rt21",
"rt22", "rt23", "rt24", "rt25", "rt26", "rt27",
"rt28", "rt29", "rt30", "rt31", "rt32"
The symbol name may optionally be prefixed with 'sig' or 'sig_' and may be in
uppercase or lowercase.
Examples
virsh send-process-signal myguest 1 15
virsh send-process-signal myguest 1 term
virsh send-process-signal myguest 1 sigterm
virsh send-process-signal myguest 1 SIG_HUP
setmem domain size [[--config] [--live] | [--current]]
Change the memory allocation for a guest domain. If --live is specified, perform a
memory balloon of a running guest. If --config is specified, affect the next boot of
a persistent guest. If --current is specified, affect the current guest state. Both
--live and --config flags may be given, but --current is exclusive. If no flag is
specified, behavior is different depending on hypervisor.
size is a scaled integer (see NOTES above); it defaults to kibibytes (blocks of 1024
bytes) unless you provide a suffix (and the older option name --kilobytes is available
as a deprecated synonym) . Libvirt rounds up to the nearest kibibyte. Some
hypervisors require a larger granularity than KiB, and requests that are not an even
multiple will be rounded up. For example, vSphere/ESX rounds the parameter up to
mebibytes (1024 kibibytes).
For Xen, you can only adjust the memory of a running domain if the domain is
paravirtualized or running the PV balloon driver.
For LXC, the value being set is the cgroups value for limit_in_bytes or the maximum
amount of user memory (including file cache). When viewing memory inside the
container, this is the /proc/meminfo "MemTotal" value. When viewing the value from the
host, use the virsh memtune command. In order to view the current memory in use and
the maximum value allowed to set memory, use the virsh dominfo command.
set-user-password domain user password [--encrypted]
Set the password for the user account in the guest domain.
If --encrypted is specified, the password is assumed to be already encrypted by the
method required by the guest OS.
For QEMU/KVM, this requires the guest agent to be configured and running.
setmaxmem domain size [[--config] [--live] | [--current]]
Change the maximum memory allocation limit for a guest domain. If --live is
specified, affect a running guest. If --config is specified, affect the next boot of
a persistent guest. If --current is specified, affect the current guest state. Both
--live and --config flags may be given, but --current is exclusive. If no flag is
specified, behavior is different depending on hypervisor.
Some hypervisors such as QEMU/KVM don't support live changes (especially increasing)
of the maximum memory limit. Even persistent configuration changes might not be
performed with some hypervisors/configuration (e.g. on NUMA enabled domains on QEMU).
For complex configuration changes use command edit instead).
size is a scaled integer (see NOTES above); it defaults to kibibytes (blocks of 1024
bytes) unless you provide a suffix (and the older option name --kilobytes is available
as a deprecated synonym) . Libvirt rounds up to the nearest kibibyte. Some
hypervisors require a larger granularity than KiB, and requests that are not an even
multiple will be rounded up. For example, vSphere/ESX rounds the parameter up to
mebibytes (1024 kibibytes).
memtune domain [--hard-limit size] [--soft-limit size] [--swap-hard-limit size]
[--min-guarantee size] [[--config] [--live] | [--current]]
Allows you to display or set the domain memory parameters. Without flags, the current
settings are displayed; with a flag, the appropriate limit is adjusted if supported by
the hypervisor. LXC and QEMU/KVM support --hard-limit, --soft-limit, and
--swap-hard-limit. --min-guarantee is supported only by ESX hypervisor. Each of
these limits are scaled integers (see NOTES above), with a default of kibibytes
(blocks of 1024 bytes) if no suffix is present. Libvirt rounds up to the nearest
kibibyte. Some hypervisors require a larger granularity than KiB, and requests that
are not an even multiple will be rounded up. For example, vSphere/ESX rounds the
parameter up to mebibytes (1024 kibibytes).
If --live is specified, affect a running guest. If --config is specified, affect the
next boot of a persistent guest. If --current is specified, affect the current guest
state. Both --live and --config flags may be given, but --current is exclusive. If no
flag is specified, behavior is different depending on hypervisor.
For QEMU/KVM, the parameters are applied to the QEMU process as a whole. Thus, when
counting them, one needs to add up guest RAM, guest video RAM, and some memory
overhead of QEMU itself. The last piece is hard to determine so one needs guess and
try.
For LXC, the displayed hard_limit value is the current memory setting from the XML or
the results from a virsh setmem command.
--hard-limit
The maximum memory the guest can use.
--soft-limit
The memory limit to enforce during memory contention.
--swap-hard-limit
The maximum memory plus swap the guest can use. This has to be more than hard-
limit value provided.
--min-guarantee
The guaranteed minimum memory allocation for the guest.
Specifying -1 as a value for these limits is interpreted as unlimited.
blkiotune domain [--weight weight] [--device-weights device-weights]
[--device-read-iops-sec device-read-iops-sec] [--device-write-iops-sec device-write-iops-
sec] [--device-read-bytes-sec device-read-bytes-sec] [--device-write-bytes-sec device-
write-bytes-sec] [[--config] [--live] | [--current]]
Display or set the blkio parameters. QEMU/KVM supports --weight. --weight is in range
[100, 1000]. After kernel 2.6.39, the value could be in the range [10, 1000].
device-weights is a single string listing one or more device/weight pairs, in the
format of /path/to/device,weight,/path/to/device,weight. Each weight is in the range
[100, 1000], [10, 1000] after kernel 2.6.39, or the value 0 to remove that device from
per-device listings. Only the devices listed in the string are modified; any existing
per-device weights for other devices remain unchanged.
device-read-iops-sec is a single string listing one or more device/read_iops_sec
pairs, int the format of /path/to/device,read_iops_sec,/path/to/device,read_iops_sec.
Each read_iops_sec is a number which type is unsigned int, value 0 to remove that
device from per-decice listing. Only the devices listed in the string are modified;
any existing per-device read_iops_sec for other devices remain unchanged.
device-write-iops-sec is a single string listing one or more device/write_iops_sec
pairs, int the format of
/path/to/device,write_iops_sec,/path/to/device,write_iops_sec. Each write_iops_sec is
a number which type is unsigned int, value 0 to remove that device from per-decice
listing. Only the devices listed in the string are modified; any existing per-device
write_iops_sec for other devices remain unchanged.
device-read-bytes-sec is a single string listing one or more device/read_bytes_sec
pairs, int the format of
/path/to/device,read_bytes_sec,/path/to/device,read_bytes_sec. Each read_bytes_sec is
a number which type is unsigned long long, value 0 to remove that device from per-
decice listing. Only the devices listed in the string are modified; any existing per-
device read_bytes_sec for other devices remain unchanged.
device-write-bytes-sec is a single string listing one or more device/write_bytes_sec
pairs, int the format of
/path/to/device,write_bytes_sec,/path/to/device,write_bytes_sec. Each write_bytes_sec
is a number which type is unsigned long long, value 0 to remove that device from per-
decice listing. Only the devices listed in the string are modified; any existing per-
device write_bytes_sec for other devices remain unchanged.
If --live is specified, affect a running guest. If --config is specified, affect the
next boot of a persistent guest. If --current is specified, affect the current guest
state. Both --live and --config flags may be given, but --current is exclusive. If no
flag is specified, behavior is different depending on hypervisor.
setvcpus domain count [--maximum] [[--config] [--live] | [--current]] [--guest]
Change the number of virtual CPUs active in a guest domain. By default, this command
works on active guest domains. To change the settings for an inactive guest domain,
use the --config flag.
The count value may be limited by host, hypervisor, or a limit coming from the
original description of the guest domain. For Xen, you can only adjust the virtual
CPUs of a running domain if the domain is paravirtualized.
If the --config flag is specified, the change is made to the stored XML configuration
for the guest domain, and will only take effect when the guest domain is next started.
If --live is specified, the guest domain must be active, and the change takes place
immediately. Both the --config and --live flags may be specified together if
supported by the hypervisor. If this command is run before the guest has finished
booting, the guest may fail to process the change.
If --current is specified, affect the current guest state.
When no flags are given, the --live flag is assumed and the guest domain must be
active. In this situation it is up to the hypervisor whether the --config flag is
also assumed, and therefore whether the XML configuration is adjusted to make the
change persistent.
If --guest is specified, then the count of cpus is modified in the guest instead of
the hypervisor. This flag is usable only for live domains and may require guest agent
to be configured in the guest.
The --maximum flag controls the maximum number of virtual cpus that can be hot-plugged
the next time the domain is booted. As such, it must only be used with the --config
flag, and not with the --live or the --current flag.
shutdown domain [--mode MODE-LIST]
Gracefully shuts down a domain. This coordinates with the domain OS to perform
graceful shutdown, so there is no guarantee that it will succeed, and may take a
variable length of time depending on what services must be shutdown in the domain.
The exact behavior of a domain when it shuts down is set by the on_shutdown parameter
in the domain's XML definition.
If domain is transient, then the metadata of any snapshots will be lost once the guest
stops running, but the snapshot contents still exist, and a new domain with the same
name and UUID can restore the snapshot metadata with snapshot-create.
By default the hypervisor will try to pick a suitable shutdown method. To specify an
alternative method, the --mode parameter can specify a comma separated list which
includes "acpi", "agent", "initctl", "signal" and "paravirt". The order in which
drivers will try each mode is undefined, and not related to the order specified to
virsh. For strict control over ordering, use a single mode at a time and repeat the
command.
start domain-name-or-uuid [--console] [--paused] [--autodestroy] [--bypass-cache]
[--force-boot] [--pass-fds N,M,...]
Start a (previously defined) inactive domain, either from the last managedsave state,
or via a fresh boot if no managedsave state is present. The domain will be paused if
the --paused option is used and supported by the driver; otherwise it will be running.
If --console is requested, attach to the console after creation. If --autodestroy is
requested, then the guest will be automatically destroyed when virsh closes its
connection to libvirt, or otherwise exits. If --bypass-cache is specified, and
managedsave state exists, the restore will avoid the file system cache, although this
may slow down the operation. If --force-boot is specified, then any managedsave state
is discarded and a fresh boot occurs.
If --pass-fds is specified, the argument is a comma separated list of open file
descriptors which should be pass on into the guest. The file descriptors will be re-
numered in the guest, starting from 3. This is only supported with container based
virtualization.
suspend domain
Suspend a running domain. It is kept in memory but won't be scheduled anymore.
resume domain
Moves a domain out of the suspended state. This will allow a previously suspended
domain to now be eligible for scheduling by the underlying hypervisor.
dompmsuspend domain target [--duration]
Suspend a running domain into one of these states (possible target values):
mem equivalent of S3 ACPI state
disk equivalent of S4 ACPI state
hybrid RAM is saved to disk but not powered off
The --duration argument specifies number of seconds before the domain is woken up
after it was suspended (see also dompmwakeup). Default is 0 for unlimited suspend
time. (This feature isn't currently supported by any hypervisor driver and 0 should be
used.).
Note that this command requires a guest agent configured and running in the domain's
guest OS.
Beware that at least for QEMU, the domain's process will be terminated when target
disk is used and a new process will be launched when libvirt is asked to wake up the
domain. As a result of this, any runtime changes, such as device hotplug or memory
settings, are lost unless such changes were made with --config flag.
dompmwakeup domain
Wakeup a domain from pmsuspended state (either suspended by dompmsuspend or from the
guest itself). Injects a wakeup into the guest that is in pmsuspended state, rather
than waiting for the previously requested duration (if any) to elapse. This operation
doesn't not necessarily fail if the domain is running.
ttyconsole domain
Output the device used for the TTY console of the domain. If the information is not
available the processes will provide an exit code of 1.
undefine domain [--managed-save] [--snapshots-metadata] [--nvram] [ {--storage volumes |
--remove-all-storage [--delete-snapshots]} --wipe-storage]
Undefine a domain. If the domain is running, this converts it to a transient domain,
without stopping it. If the domain is inactive, the domain configuration is removed.
The --managed-save flag guarantees that any managed save image (see the managedsave
command) is also cleaned up. Without the flag, attempts to undefine a domain with a
managed save image will fail.
The --snapshots-metadata flag guarantees that any snapshots (see the snapshot-list
command) are also cleaned up when undefining an inactive domain. Without the flag,
attempts to undefine an inactive domain with snapshot metadata will fail. If the
domain is active, this flag is ignored.
The --nvram flag ensures no nvram (/domain/os/nvram/) file is left behind. If the
domain has an nvram file and the flag is omitted, the undefine will fail.
The --storage flag takes a parameter volumes, which is a comma separated list of
volume target names or source paths of storage volumes to be removed along with the
undefined domain. Volumes can be undefined and thus removed only on inactive domains.
Volume deletion is only attempted after the domain is undefined; if not all of the
requested volumes could be deleted, the error message indicates what still remains
behind. If a volume path is not found in the domain definition, it's treated as if the
volume was successfully deleted. Only volumes managed by libvirt in storage pools can
be removed this way. (See domblklist for list of target names associated to a
domain). Example: --storage vda,/path/to/storage.img
The --remove-all-storage flag specifies that all of the domain's storage volumes
should be deleted.
The --delete-snapshots flag specifies that any snapshots associated with the storage
volume should be deleted as well. Requires the --remove-all-storage flag to be
provided. Not all storage drivers support this option, presently only rbd.
The flag --wipe-storage specifies that the storage volumes should be wiped before
removal.
NOTE: For an inactive domain, the domain name or UUID must be used as the domain.
vcpucount domain [{--maximum | --active} {--config | --live | --current}] [--guest]
Print information about the virtual cpu counts of the given domain. If no flags are
specified, all possible counts are listed in a table; otherwise, the output is limited
to just the numeric value requested. For historical reasons, the table lists the
label "current" on the rows that can be queried in isolation via the --active flag,
rather than relating to the --current flag.
--maximum requests information on the maximum cap of vcpus that a domain can add via
setvcpus, while --active shows the current usage; these two flags cannot both be
specified. --config requires a persistent domain and requests information regarding
the next time the domain will be booted, --live requires a running domain and lists
current values, and --current queries according to the current state of the domain
(corresponding to --live if running, or --config if inactive); these three flags are
mutually exclusive.
If --guest is specified, then the count of cpus is reported from the perspective of
the guest. This flag is usable only for live domains and may require guest agent to be
configured in the guest.
vcpuinfo domain [--pretty]
Returns basic information about the domain virtual CPUs, like the number of vCPUs, the
running time, the affinity to physical processors.
With --pretty, cpu affinities are shown as ranges.
vcpupin domain [vcpu] [cpulist] [[--live] [--config] | [--current]]
Query or change the pinning of domain VCPUs to host physical CPUs. To pin a single
vcpu, specify cpulist; otherwise, you can query one vcpu or omit vcpu to list all at
once.
cpulist is a list of physical CPU numbers. Its syntax is a comma separated list and a
special markup using '-' and '^' (ex. '0-4', '0-3,^2') can also be allowed. The '-'
denotes the range and the '^' denotes exclusive. For pinning the vcpu to all physical
cpus specify 'r' as a cpulist. If --live is specified, affect a running guest. If
--config is specified, affect the next boot of a persistent guest. If --current is
specified, affect the current guest state. Both --live and --config flags may be
given if cpulist is present, but --current is exclusive. If no flag is specified,
behavior is different depending on hypervisor.
Note: The expression is sequentially evaluated, so "0-15,^8" is identical to
"9-14,0-7,15" but not identical to "^8,0-15".
emulatorpin domain [cpulist] [[--live] [--config] | [--current]]
Query or change the pinning of domain's emulator threads to host physical CPUs.
See vcpupin for cpulist.
If --live is specified, affect a running guest. If --config is specified, affect the
next boot of a persistent guest. If --current is specified, affect the current guest
state. Both --live and --config flags may be given if cpulist is present, but
--current is exclusive. If no flag is specified, behavior is different depending on
hypervisor.
vncdisplay domain
Output the IP address and port number for the VNC display. If the information is not
available the processes will provide an exit code of 1.
DEVICE COMMANDS
The following commands manipulate devices associated to domains. The domain can be
specified as a short integer, a name or a full UUID. To better understand the values
allowed as options for the command reading the documentation at
<http://libvirt.org/formatdomain.html> on the format of the device sections to get the
most accurate set of accepted values.
attach-device domain FILE [[[--live] [--config] | [--current]] | [--persistent]]
Attach a device to the domain, using a device definition in an XML file using a device
definition element such as <disk> or <interface> as the top-level element. See the
documentation at <http://libvirt.org/formatdomain.html#elementsDevices> to learn about
libvirt XML format for a device. If --config is specified the command alters the
persistent domain configuration with the device attach taking effect the next time
libvirt starts the domain. For cdrom and floppy devices, this command only replaces
the media within an existing device; consider using update-device for this usage. For
passthrough host devices, see also nodedev-detach, needed if the PCI device does not
use managed mode.
If --live is specified, affect a running domain. If --config is specified, affect the
next startup of a persistent domain. If --current is specified, affect the current
domain state. Both --live and --config flags may be given, but --current is
exclusive. When no flag is specified legacy API is used whose behavior depends on the
hypervisor driver.
For compatibility purposes, --persistent behaves like --config for an offline domain,
and like --live --config for a running domain.
Note: using of partial device definition XML files may lead to unexpected results as
some fields may be autogenerated and thus match devices other than expected.
attach-disk domain source target [[[--live] [--config] | [--current]] | [--persistent]]
[--targetbus bus] [--driver driver] [--subdriver subdriver] [--iothread iothread] [--cache
cache] [--type type] [--mode mode] [--sourcetype sourcetype] [--serial serial] [--wwn wwn]
[--rawio] [--address address] [--multifunction] [--print-xml]
Attach a new disk device to the domain. source is path for the files and devices.
target controls the bus or device under which the disk is exposed to the guest OS. It
indicates the "logical" device name; the optional targetbus attribute specifies the
type of disk device to emulate; possible values are driver specific, with typical
values being ide, scsi, virtio, xen, usb, sata, or sd, if omitted, the bus type is
inferred from the style of the device name (e.g. a device named 'sda' will typically
be exported using a SCSI bus). driver can be file, tap or phy for the Xen hypervisor
depending on the kind of access; or qemu for the QEMU emulator. Further details to
the driver can be passed using subdriver. For Xen subdriver can be aio, while for QEMU
subdriver should match the format of the disk source, such as raw or qcow2.
Hypervisor default will be used if subdriver is not specified. However, the default
may not be correct, esp. for QEMU as for security reasons it is configured not to
detect disk formats. type can indicate lun, cdrom or floppy as alternative to the
disk default, although this use only replaces the media within the existing virtual
cdrom or floppy device; consider using update-device for this usage instead. mode can
specify the two specific mode readonly or shareable. sourcetype can indicate the type
of source (block|file) cache can be one of "default", "none", "writethrough",
"writeback", "directsync" or "unsafe". iothread is the number within the range of
domain IOThreads to which this disk may be attached (QEMU only). serial is the serial
of disk device. wwn is the wwn of disk device. rawio indicates the disk needs rawio
capability. address is the address of disk device in the form of
pci:domain.bus.slot.function, scsi:controller.bus.unit, ide:controller.bus.unit or
ccw:cssid.ssid.devno. Virtio-ccw devices must have their cssid set to 0xfe.
multifunction indicates specified pci address is a multifunction pci device address.
If --print-xml is specified, then the XML of the disk that would be attached is
printed instead.
If --live is specified, affect a running domain. If --config is specified, affect the
next startup of a persistent domain. If --current is specified, affect the current
domain state. Both --live and --config flags may be given, but --current is
exclusive. When no flag is specified legacy API is used whose behavior depends on the
hypervisor driver.
For compatibility purposes, --persistent behaves like --config for an offline domain,
and like --live --config for a running domain. Likewise, --shareable is an alias for
--mode shareable.
attach-interface domain type source [[[--live] [--config] | [--current]] | [--persistent]]
[--target target] [--mac mac] [--script script] [--model model] [--inbound
average,peak,burst,floor] [--outbound average,peak,burst] [--managed] [--print-xml]
Attach a new network interface to the domain.
type can be one of the:
network to indicate connection via a libvirt virtual network,
bridge to indicate connection via a bridge device on the host,
direct to indicate connection directly to one of the host's network interfaces or
bridges,
hostdev to indicate connection using a passthrough of PCI device on the host.
source indicates the source of the connection. The source depends on the type of the
interface:
network name of the virtual network,
bridge the name of the bridge device,
direct the name of the host's interface or bridge,
hostdev the PCI address of the host's interface formatted as
domain:bus:slot.function.
--target is used to specify the tap/macvtap device to be used to connect the domain to
the source. Names starting with 'vnet' are considered as auto-generated and are
blanked out/regenerated each time the interface is attached.
--mac specifies the MAC address of the network interface; if a MAC address is not
given, a new address will be automatically generated (and stored in the persistent
configuration if "--config" is given on the command line).
--script is used to specify a path to a custom script to be called while attaching to
a bridge - this will be called instead of the default script not in addition to it.
This is valid only for interfaces of bridge type and only for Xen domains.
--model specifies the network device model to be presented to the domain.
--inbound and --outbound control the bandwidth of the interface. At least one from
the average, floor pair must be specified. The other two peak and burst are optional,
so "average,peak", "average,,burst", "average,,,floor", "average" and ",,,floor" are
also legal. Values for average, floor and peak are expressed in kilobytes per second,
while burst is expressed in kilobytes in a single burst at peak speed as described in
the Network XML documentation at <http://libvirt.org/formatnetwork.html#elementQoS>.
--managed is usable only for hostdev type and tells libvirt that the interface should
be managed, which means detached and reattached from/to the host by libvirt.
If --print-xml is specified, then the XML of the interface that would be attached is
printed instead.
If --live is specified, affect a running domain. If --config is specified, affect the
next startup of a persistent domain. If --current is specified, affect the current
domain state. Both --live and --config flags may be given, but --current is
exclusive. When no flag is specified legacy API is used whose behavior depends on the
hypervisor driver.
For compatibility purposes, --persistent behaves like --config for an offline domain,
and like --live --config for a running domain.
Note: the optional target value is the name of a device to be created as the back-end
on the node. If not provided a device named "vnetN" or "vifN" will be created
automatically.
detach-device domain FILE [[[--live] [--config] | [--current]] | [--persistent]]
Detach a device from the domain, takes the same kind of XML descriptions as command
attach-device. For passthrough host devices, see also nodedev-reattach, needed if the
device does not use managed mode.
Note: The supplied XML description of the device should be as specific as its
definition in the domain XML. The set of attributes used to match the device are
internal to the drivers. Using a partial definition, or attempting to detach a device
that is not present in the domain XML, but shares some specific attributes with one
that is present, may lead to unexpected results.
If --live is specified, affect a running domain. If --config is specified, affect the
next startup of a persistent domain. If --current is specified, affect the current
domain state. Both --live and --config flags may be given, but --current is
exclusive. When no flag is specified legacy API is used whose behavior depends on the
hypervisor driver.
For compatibility purposes, --persistent behaves like --config for an offline domain,
and like --live --config for a running domain.
Note that older versions of virsh used --config as an alias for --persistent.
detach-disk domain target [[[--live] [--config] | [--current]] | [--persistent]]
Detach a disk device from a domain. The target is the device as seen from the domain.
If --live is specified, affect a running domain. If --config is specified, affect the
next startup of a persistent domain. If --current is specified, affect the current
domain state. Both --live and --config flags may be given, but --current is
exclusive. When no flag is specified legacy API is used whose behavior depends on the
hypervisor driver.
For compatibility purposes, --persistent behaves like --config for an offline domain,
and like --live --config for a running domain.
Note that older versions of virsh used --config as an alias for --persistent.
detach-interface domain type [--mac mac] [[[--live] [--config] | [--current]] |
[--persistent]]
Detach a network interface from a domain. type can be either network to indicate a
physical network device or bridge to indicate a bridge to a device. It is recommended
to use the mac option to distinguish between the interfaces if more than one are
present on the domain.
If --live is specified, affect a running domain. If --config is specified, affect the
next startup of a persistent domain. If --current is specified, affect the current
domain state. Both --live and --config flags may be given, but --current is
exclusive. When no flag is specified legacy API is used whose behavior depends on the
hypervisor driver.
For compatibility purposes, --persistent behaves like --config for an offline domain,
and like --live --config for a running domain.
Note that older versions of virsh used --config as an alias for --persistent.
update-device domain file [--force] [[[--live] [--config] | [--current]] | [--persistent]]
Update the characteristics of a device associated with domain, based on the device
definition in an XML file. The --force option can be used to force device update,
e.g., to eject a CD-ROM even if it is locked/mounted in the domain. See the
documentation at <http://libvirt.org/formatdomain.html#elementsDevices> to learn about
libvirt XML format for a device.
If --live is specified, affect a running domain. If --config is specified, affect the
next startup of a persistent domain. If --current is specified, affect the current
domain state. Both --live and --config flags may be given, but --current is
exclusive. Not specifying any flag is the same as specifying --current.
For compatibility purposes, --persistent behaves like --config for an offline domain,
and like --live --config for a running domain.
Note that older versions of virsh used --config as an alias for --persistent.
Note: using of partial device definition XML files may lead to unexpected results as
some fields may be autogenerated and thus match devices other than expected.
change-media domain path [--eject] [--insert] [--update] [source] [--force] [[--live]
[--config] | [--current]] [--print-xml] [--block]
Change media of CDROM or floppy drive. path can be the fully-qualified path or the
unique target name (<target dev='hdc'>) of the disk device. source specifies the path
of the media to be inserted or updated. Flag --block allows to set the backing type in
case a block device is used as media for the CDROM or floppy drive instead of a file.
--eject indicates the media will be ejected. --insert indicates the media will be
inserted. source must be specified. If the device has source (e.g. <source
file='media'>), and source is not specified, --update is equal to --eject. If the
device has no source, and source is specified, --update is equal to --insert. If the
device has source, and source is specified, --update behaves like combination of
--eject and --insert. If none of --eject, --insert, and --update is specified,
--update is used by default. The --force option can be used to force media changing.
If --live is specified, alter live configuration of running guest. If --config is
specified, alter persistent configuration, effect observed on next boot. --current
can be either or both of live and config, depends on the hypervisor's implementation.
Both --live and --config flags may be given, but --current is exclusive. If no flag is
specified, behavior is different depending on hypervisor. If --print-xml is
specified, the XML that would be used to change media is printed instead of changing
the media.
NODEDEV COMMANDS
The following commands manipulate host devices that are intended to be passed through to
guest domains via <hostdev> elements in a domain's <devices> section. A node device key
is generally specified by the bus name followed by its address, using underscores between
all components, such as pci_0000_00_02_1, usb_1_5_3, or net_eth1_00_27_13_6a_fe_00. The
nodedev-list gives the full list of host devices that are known to libvirt, although this
includes devices that cannot be assigned to a guest (for example, attempting to detach the
PCI device that controls the host's hard disk controller where the guest's disk images
live could cause the host system to lock up or reboot).
For more information on node device definition see: <http://libvirt.org/formatnode.html>.
Passthrough devices cannot be simultaneously used by the host and its guest domains, nor
by multiple active guests at once. If the <hostdev> description of a PCI device includes
the attribute managed='yes', and the hypervisor driver supports it, then the device is in
managed mode, and attempts to use that passthrough device in an active guest will
automatically behave as if nodedev-detach (guest start, device hot-plug) and nodedev-
reattach (guest stop, device hot-unplug) were called at the right points. If a PCI device
is not marked as managed, then it must manually be detached before guests can use it, and
manually reattached to be returned to the host. Also, if a device is manually detached,
then the host does not regain control of the device without a matching reattach, even if
the guests use the device in managed mode.
nodedev-create FILE
Create a device on the host node that can then be assigned to virtual machines.
Normally, libvirt is able to automatically determine which host nodes are available
for use, but this allows registration of host hardware that libvirt did not
automatically detect. file contains xml for a top-level <device> description of a
node device.
nodedev-destroy device
Destroy (stop) a device on the host. device can be either device name or wwn pair in
"wwnn,wwpn" format (only works for vHBA currently). Note that this makes libvirt quit
managing a host device, and may even make that device unusable by the rest of the
physical host until a reboot.
nodedev-detach nodedev [--driver backend_driver]
Detach nodedev from the host, so that it can safely be used by guests via <hostdev>
passthrough. This is reversed with nodedev-reattach, and is done automatically for
managed devices. For compatibility purposes, this command can also be spelled
nodedev-dettach.
Different backend drivers expect the device to be bound to different dummy devices.
For example, QEMU's "kvm" backend driver (the default) expects the device to be bound
to pci-stub, but its "vfio" backend driver expects the device to be bound to vfio-pci.
The --driver parameter can be used to specify the desired backend driver.
nodedev-dumpxml device
Dump a <device> XML representation for the given node device, including such
information as the device name, which bus owns the device, the vendor and product id,
and any capabilities of the device usable by libvirt (such as whether device reset is
supported). device can be either device name or wwn pair in "wwnn,wwpn" format (only
works for HBA).
nodedev-list cap --tree
List all of the devices available on the node that are known by libvirt. cap is used
to filter the list by capability types, the types must be separated by comma, e.g.
--cap pci,scsi, valid capability types include 'system', 'pci', 'usb_device', 'usb',
'net', 'scsi_host', 'scsi_target', 'scsi', 'storage', 'fc_host', 'vports',
'scsi_generic'. If --tree is used, the output is formatted in a tree representing
parents of each node. cap and --tree are mutually exclusive.
nodedev-reattach nodedev
Declare that nodedev is no longer in use by any guests, and that the host can resume
normal use of the device. This is done automatically for PCI devices in managed mode
and USB devices, but must be done explicitly to match any explicit nodedev-detach.
nodedev-reset nodedev
Trigger a device reset for nodedev, useful prior to transferring a node device between
guest passthrough or the host. Libvirt will often do this action implicitly when
required, but this command allows an explicit reset when needed.
VIRTUAL NETWORK COMMANDS
The following commands manipulate networks. Libvirt has the capability to define virtual
networks which can then be used by domains and linked to actual network devices. For more
detailed information about this feature see the documentation at
<http://libvirt.org/formatnetwork.html> . Many of the commands for virtual networks are
similar to the ones used for domains, but the way to name a virtual network is either by
its name or UUID.
net-autostart network [--disable]
Configure a virtual network to be automatically started at boot. The --disable option
disable autostarting.
net-create file
Create a transient (temporary) virtual network from an XML file and instantiate
(start) the network. See the documentation at <http://libvirt.org/formatnetwork.html>
to get a description of the XML network format used by libvirt.
net-define file
Define an inactive persistent virtual network or modify an existing persistent one
from the XML file.
net-destroy network
Destroy (stop) a given transient or persistent virtual network specified by its name
or UUID. This takes effect immediately.
net-dumpxml network [--inactive]
Output the virtual network information as an XML dump to stdout. If --inactive is
specified, then physical functions are not expanded into their associated virtual
functions.
net-edit network
Edit the XML configuration file for a network.
This is equivalent to:
virsh net-dumpxml --inactive network > network.xml
vi network.xml (or make changes with your other text editor)
virsh net-define network.xml
except that it does some error checking.
The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and
defaults to "vi".
net-event {[network] event [--loop] [--timeout seconds] [--timestamp] | --list}
Wait for a class of network events to occur, and print appropriate details of events
as they happen. The events can optionally be filtered by network. Using --list as
the only argument will provide a list of possible event values known by this client,
although the connection might not allow registering for all these events.
By default, this command is one-shot, and returns success once an event occurs; you
can send SIGINT (usually via "Ctrl-C") to quit immediately. If --timeout is
specified, the command gives up waiting for events after seconds have elapsed. With
--loop, the command prints all events until a timeout or interrupt key.
When --timestamp is used, a human-readable timestamp will be printed before the event.
net-info network
Returns basic information about the network object.
net-list [--inactive | --all] { [--table] | --name | --uuid } [--persistent]
[<--transient>] [--autostart] [<--no-autostart>]
Returns the list of active networks, if --all is specified this will also include
defined but inactive networks, if --inactive is specified only the inactive ones will
be listed. You may also want to filter the returned networks by --persistent to list
the persistent ones, --transient to list the transient ones, --autostart to list the
ones with autostart enabled, and --no-autostart to list the ones with autostart
disabled.
If --name is specified, network names are printed instead of the table formatted one
per line. If --uuid is specified network's UUID's are printed instead of names. Flag
--table specifies that the legacy table-formatted output should be used. This is the
default. All of these are mutually exclusive.
NOTE: When talking to older servers, this command is forced to use a series of API
calls with an inherent race, where a pool might not be listed or might appear more
than once if it changed state between calls while the list was being collected. Newer
servers do not have this problem.
net-name network-UUID
Convert a network UUID to network name.
net-start network
Start a (previously defined) inactive network.
net-undefine network
Undefine the configuration for a persistent network. If the network is active, make it
transient.
net-uuid network-name
Convert a network name to network UUID.
net-update network command section xml [--parent-index index] [[--live] [--config] |
[--current]]
Update the given section of an existing network definition, with the changes
optionally taking effect immediately, without needing to destroy and re-start the
network.
command is one of "add-first", "add-last", "add" (a synonym for add-last), "delete",
or "modify".
section is one of "bridge", "domain", "ip", "ip-dhcp-host", "ip-dhcp-range",
"forward", "forward-interface", "forward-pf", "portgroup", "dns-host", "dns-txt", or
"dns-srv", each section being named by a concatenation of the xml element hierarchy
leading to the element being changed. For example, "ip-dhcp-host" will change a <host>
element that is contained inside a <dhcp> element inside an <ip> element of the
network.
xml is either the text of a complete xml element of the type being changed (e.g.
"<host mac="00:11:22:33:44:55' ip='1.2.3.4'/>", or the name of a file that contains a
complete xml element. Disambiguation is done by looking at the first character of the
provided text - if the first character is "<", it is xml text, if the first character
is not "<", it is the name of a file that contains the xml text to be used.
The --parent-index option is used to specify which of several parent elements the
requested element is in (0-based). For example, a dhcp <host> element could be in any
one of multiple <ip> elements in the network; if a parent-index isn't provided, the
"most appropriate" <ip> element will be selected (usually the only one that already
has a <dhcp> element), but if --parent-index is given, that particular instance of
<ip> will get the modification.
If --live is specified, affect a running network. If --config is specified, affect
the next startup of a persistent network. If --current is specified, affect the
current network state. Both --live and --config flags may be given, but --current is
exclusive. Not specifying any flag is the same as specifying --current.
net-dhcp-leases network [mac]
Get a list of dhcp leases for all network interfaces connected to the given virtual
network or limited output just for one interface if mac is specified.
INTERFACE COMMANDS
The following commands manipulate host interfaces. Often, these host interfaces can then
be used by name within domain <interface> elements (such as a system-created bridge
interface), but there is no requirement that host interfaces be tied to any particular
guest configuration XML at all.
Many of the commands for host interfaces are similar to the ones used for domains, and the
way to name an interface is either by its name or its MAC address. However, using a MAC
address for an iface argument only works when that address is unique (if an interface and
a bridge share the same MAC address, which is often the case, then using that MAC address
results in an error due to ambiguity, and you must resort to a name instead).
iface-bridge interface bridge [--no-stp] [delay] [--no-start]
Create a bridge device named bridge, and attach the existing network device interface
to the new bridge. The new bridge defaults to starting immediately, with STP enabled
and a delay of 0; these settings can be altered with --no-stp, --no-start, and an
integer number of seconds for delay. All IP address configuration of interface will be
moved to the new bridge device.
See also iface-unbridge for undoing this operation.
iface-define file
Define an inactive persistent physical host interface or modify an existing persistent
one from the XML file.
iface-destroy interface
Destroy (stop) a given host interface, such as by running "if-down" to disable that
interface from active use. This takes effect immediately.
iface-dumpxml interface [--inactive]
Output the host interface information as an XML dump to stdout. If --inactive is
specified, then the output reflects the persistent state of the interface that will be
used the next time it is started.
iface-edit interface
Edit the XML configuration file for a host interface.
This is equivalent to:
virsh iface-dumpxml iface > iface.xml
vi iface.xml (or make changes with your other text editor)
virsh iface-define iface.xml
except that it does some error checking.
The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and
defaults to "vi".
iface-list [--inactive | --all]
Returns the list of active host interfaces. If --all is specified this will also
include defined but inactive interfaces. If --inactive is specified only the inactive
ones will be listed.
iface-name interface
Convert a host interface MAC to interface name, if the MAC address is unique among the
host's interfaces.
interface specifies the interface MAC address.
iface-mac interface
Convert a host interface name to MAC address.
interface specifies the interface name.
iface-start interface
Start a (previously defined) host interface, such as by running "if-up".
iface-unbridge bridge [--no-start]
Tear down a bridge device named bridge, releasing its underlying interface back to
normal usage, and moving all IP address configuration from the bridge device to the
underlying device. The underlying interface is restarted unless --no-start is
present; this flag is present for symmetry, but generally not recommended.
See also iface-bridge for creating a bridge.
iface-undefine interface
Undefine the configuration for an inactive host interface.
iface-begin
Create a snapshot of current host interface settings, which can later be committed
(iface-commit) or restored (iface-rollback). If a snapshot already exists, then this
command will fail until the previous snapshot has been committed or restored.
Undefined behavior results if any external changes are made to host interfaces outside
of the libvirt API between the beginning of a snapshot and its eventual commit or
rollback.
iface-commit
Declare all changes since the last iface-begin as working, and delete the rollback
point. If no interface snapshot has already been started, then this command will
fail.
iface-rollback
Revert all host interface settings back to the state recorded in the last iface-begin.
If no interface snapshot has already been started, then this command will fail.
Rebooting the host also serves as an implicit rollback point.
STORAGE POOL COMMANDS
The following commands manipulate storage pools. Libvirt has the capability to manage
various storage solutions, including files, raw partitions, and domain-specific formats,
used to provide the storage volumes visible as devices within virtual machines. For more
detailed information about this feature, see the documentation at
<http://libvirt.org/formatstorage.html> . Many of the commands for pools are similar to
the ones used for domains.
find-storage-pool-sources type [srcSpec]
Returns XML describing all possible available storage pool sources that could be used
to create or define a storage pool of a given type. If srcSpec is provided, it is a
file that contains XML to further restrict the query for pools.
Not all storage pools support discovery in this manner. Furthermore, for those that do
support discovery, only specific XML elements are required in order to return valid
data, while other elements and even attributes of some elements are ignored since they
are not necessary to find the pool based on the search criteria. The following lists
the supported type options and the expected minimal XML elements used to perform the
search.
For a "netfs" or "gluster" pool, the minimal expected XML required is the <host>
element with a "name" attribute describing the IP address or hostname to be used to
find the pool. The "port" attribute will be ignored as will any other provided XML
elements in srcSpec.
For a "logical" pool, the contents of the srcSpec file are ignored, although if
provided the file must at least exist.
For an "iscsi" pool, the minimal expect XML required is the <host> element with a
"name" attribute describing the IP address or hostname to be used to find the pool
(the iSCSI server address). Optionally, the "port" attribute may be provided, although
it will default to 3260. Optionally, an <initiator> XML element with a "name"
attribute may be provided to further restrict the iSCSI target search to a specific
initiator for multi-iqn iSCSI storage pools.
find-storage-pool-sources-as type [host] [port] [initiator]
Rather than providing srcSpec XML file for find-storage-pool-sources use this command
option in order to have virsh generate the query XML file using the optional
arguments. The command will return the same output XML as find-storage-pool-sources.
Use host to describe a specific host to use for networked storage, such as netfs,
gluster, and iscsi type pools.
Use port to further restrict which networked port to utilize for the connection if
required by the specific storage backend, such as iscsi.
Use initiator to further restrict the iscsi type pool searches to specific target
initiators.
pool-autostart pool-or-uuid [--disable]
Configure whether pool should automatically start at boot.
pool-build pool-or-uuid [--overwrite] [--no-overwrite]
Build a given pool.
Options --overwrite and --no-overwrite can only be used for pool-build a filesystem or
disk pool. For a file system pool if neither of them is specified, pool-build makes
the directory. If --no-overwrite is specified, it probes to determine if a filesystem
already exists on the target device, returning an error if exists, or using mkfs to
format the target device if not. If --overwrite is specified, mkfs is always executed
and any existing data on the target device is overwritten unconditionally. For a disk
pool, if neither of them is specified or --no-overwrite is specified, pool-build will
use 'parted --print' in order to determine if the disk already has a label before
attempting to create one. Only if a disk does not already have one will a label be
created. If --overwrite is specified or it's been determined that the disk doesn't
already have one, 'parted mklabel' will be used to create a label of the format
specified by the pool source format type or "dos" if not specified for the pool.
pool-create file [--build] [[--overwrite] | [--no-overwrite]]
Create and start a pool object from the XML file.
[--build] [[--overwrite] | [--no-overwrite]] perform a pool-build after creation in
order to remove the need for a follow-up command to build the pool. The --overwrite
and --no-overwrite flags follow the same rules as pool-build. If just --build is
provided, then pool-build is called with no flags.
pool-create-as name type [--print-xml] [--source-host hostname] [--source-path path]
[--source-dev path] [--source-name name] [--target path] [--source-format format]
[--auth-type authtype --auth-username username --secret-usage usage] [[--adapter-name
name] | [--adapter-wwnn --adapter-wwpn] [--adapter-parent parent]] [--build]
[[--overwrite] | [--no-overwrite]]
Create and start a pool object name from the raw parameters. If --print-xml is
specified, then print the XML of the pool object without creating the pool.
Otherwise, the pool has the specified type. When using pool-create-as for a pool of
type "disk", the existing partitions found on the --source-dev path will be used to
populate the disk pool. Therefore, it is suggested to use pool-define-as and pool-
build with the --overwrite in order to properly initialize the disk pool.
[--source-host hostname] provides the source hostname for pools backed by storage from
a remote server (pool types netfs, iscsi, rbd, sheepdog, gluster).
[--source-path path] provides the source directory path for pools backed by
directories (pool type dir).
[--source-dev path] provides the source path for pools backed by physical devices
(pool types fs, logical, disk, iscsi, zfs).
[--source-name name] provides the source name for pools backed by storage from a named
element (pool types logical, rbd, sheepdog, gluster).
[--target path] is the path for the mapping of the storage pool into the host file
system.
[--source-format format] provides information about the format of the pool (pool types
fs, netfs, disk, logical).
[--auth-type authtype --auth-username username --secret-usage usage] provides the
elements required to generate authentication credentials for the storage pool. The
authtype is either chap for iscsi type pools or ceph for rbd type pools.
[--adapter-name name] defines the scsi_hostN adapter name to be used for the scsi_host
adapter type pool.
[--adapter-wwnn --adapter-wwpn [--adapter-parent parent]] defines the wwnn and wwpn to
be used for the fc_host adapter type pool. The parent optionally provides the name of
the scsi_hostN node device to be used for the vHBA.
[--build] [[--overwrite] | [--no-overwrite]] perform a pool-build after creation in
order to remove the need for a follow-up command to build the pool. The --overwrite
and --no-overwrite flags follow the same rules as pool-build. If just --build is
provided, then pool-build is called with no flags.
pool-define file
Define an inactive persistent storage pool or modify an existing persistent one from
the XML file.
pool-define-as name type [--print-xml] [--source-host hostname] [--source-path path]
[--source-dev path] [--source-name name] [--target path] [--source-format format]
[--auth-type authtype --auth-username username --secret-usage usage] [[--adapter-name
name] | [--adapter-wwnn --adapter-wwpn] [--adapter-parent parent]]
Create, but do not start, a pool object name from the raw parameters. If --print-xml
is specified, then print the XML of the pool object without defining the pool.
Otherwise, the pool has the specified type.
Use the same arguments as pool-create-as, except for the --build, --overwrite, and
--no-overwrite options.
pool-destroy pool-or-uuid
Destroy (stop) a given pool object. Libvirt will no longer manage the storage
described by the pool object, but the raw data contained in the pool is not changed,
and can be later recovered with pool-create.
pool-delete pool-or-uuid
Destroy the resources used by a given pool object. This operation is non-recoverable.
The pool object will still exist after this command, ready for the creation of new
storage volumes.
pool-dumpxml [--inactive] pool-or-uuid
Returns the XML information about the pool object. --inactive tells virsh to dump
pool configuration that will be used on next start of the pool as opposed to the
current pool configuration.
pool-edit pool-or-uuid
Edit the XML configuration file for a storage pool.
This is equivalent to:
virsh pool-dumpxml pool > pool.xml
vi pool.xml (or make changes with your other text editor)
virsh pool-define pool.xml
except that it does some error checking.
The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and
defaults to "vi".
pool-info pool-or-uuid
Returns basic information about the pool object.
pool-list [--inactive] [--all] [--persistent] [--transient] [--autostart] [--no-autostart]
[[--details] [<type>]
List pool objects known to libvirt. By default, only active pools are listed;
--inactive lists just the inactive pools, and --all lists all pools.
In addition, there are several sets of filtering flags. --persistent is to list the
persistent pools, --transient is to list the transient pools. --autostart lists the
autostarting pools, --no-autostart lists the pools with autostarting disabled.
You may also want to list pools with specified types using type, the pool types must
be separated by comma, e.g. --type dir,disk. The valid pool types include 'dir', 'fs',
'netfs', 'logical', 'disk', 'iscsi', 'scsi', 'mpath', 'rbd', 'sheepdog' and 'gluster'.
The --details option instructs virsh to additionally display pool persistence and
capacity related information where available.
NOTE: When talking to older servers, this command is forced to use a series of API
calls with an inherent race, where a pool might not be listed or might appear more
than once if it changed state between calls while the list was being collected. Newer
servers do not have this problem.
pool-name uuid
Convert the uuid to a pool name.
pool-refresh pool-or-uuid
Refresh the list of volumes contained in pool.
pool-start pool-or-uuid [--build] [[--overwrite] | [--no-overwrite]]
Start the storage pool, which is previously defined but inactive.
[--build] [[--overwrite] | [--no-overwrite]] perform a pool-build prior to pool-start
to ensure the pool environment is in an expected state rather than needing to run the
build command prior to startup. The --overwrite and --no-overwrite flags follow the
same rules as pool-build. If just --build is provided, then pool-build is called with
no flags.
Note: A storage pool that relies on remote resources such as an "iscsi" or a (v)HBA
backed "scsi" pool may need to be refreshed multiple times in order to have all the
volumes detected (see pool-refresh). This is because the corresponding volume devices
may not be present in the host's filesystem during the initial pool startup or the
current refresh attempt. The number of refresh retries is dependent upon the network
connection and the time the host takes to export the corresponding devices.
pool-undefine pool-or-uuid
Undefine the configuration for an inactive pool.
pool-uuid pool
Returns the UUID of the named pool.
VOLUME COMMANDS
vol-create pool-or-uuid FILE [--prealloc-metadata]
Create a volume from an XML <file>. pool-or-uuid is the name or UUID of the storage
pool to create the volume in. FILE is the XML <file> with the volume definition. An
easy way to create the XML <file> is to use the vol-dumpxml command to obtain the
definition of a pre-existing volume. [--prealloc-metadata] preallocate metadata (for
qcow2 images which don't support full allocation). This option creates a sparse image
file with metadata, resulting in higher performance compared to images with no
preallocation and only slightly higher initial disk space usage.
Example
virsh vol-dumpxml --pool storagepool1 appvolume1 > newvolume.xml
vi newvolume.xml (or make changes with your other text editor)
virsh vol-create differentstoragepool newvolume.xml
vol-create-from pool-or-uuid FILE [--inputpool pool-or-uuid] vol-name-or-key-or-path
[--prealloc-metadata] [--reflink]
Create a volume, using another volume as input. pool-or-uuid is the name or UUID of
the storage pool to create the volume in. FILE is the XML <file> with the volume
definition. --inputpool pool-or-uuid is the name or uuid of the storage pool the
source volume is in. vol-name-or-key-or-path is the name or key or path of the source
volume. [--prealloc-metadata] preallocate metadata (for qcow2 images which don't
support full allocation). This option creates a sparse image file with metadata,
resulting in higher performance compared to images with no preallocation and only
slightly higher initial disk space usage. When --reflink is specified, perform a COW
lightweight copy, where the data blocks are copied only when modified. If this is not
possible, the copy fails.
vol-create-as pool-or-uuid name capacity [--allocation size] [--format string]
[--backing-vol vol-name-or-key-or-path] [--backing-vol-format string]
[--prealloc-metadata]
Create a volume from a set of arguments. pool-or-uuid is the name or UUID of the
storage pool to create the volume in. name is the name of the new volume. For a disk
pool, this must match the partition name as determined from the pool's source device
path and the next available partition. For example, a source device path of /dev/sdb
and there are no partitions on the disk, then the name must be sdb1 with the next name
being sdb2 and so on. capacity is the size of the volume to be created, as a scaled
integer (see NOTES above), defaulting to bytes if there is no suffix. --allocation
size is the initial size to be allocated in the volume, also as a scaled integer
defaulting to bytes. --format string is used in file based storage pools to specify
the volume file format to use; raw, bochs, qcow, qcow2, vmdk, qed. Use extended for
disk storage pools in order to create an extended partition (other values are validity
checked but not preserved when libvirtd is restarted or the pool is refreshed).
--backing-vol vol-name-or-key-or-path is the source backing volume to be used if
taking a snapshot of an existing volume. --backing-vol-format string is the format of
the snapshot backing volume; raw, bochs, qcow, qcow2, qed, vmdk, host_device. These
are, however, meant for file based storage pools. [--prealloc-metadata] preallocate
metadata (for qcow2 images which don't support full allocation). This option creates a
sparse image file with metadata, resulting in higher performance compared to images
with no preallocation and only slightly higher initial disk space usage.
vol-clone [--pool pool-or-uuid] vol-name-or-key-or-path name [--prealloc-metadata]
[--reflink]
Clone an existing volume. Less powerful, but easier to type, version of vol-create-
from. --pool pool-or-uuid is the name or UUID of the storage pool to create the
volume in. vol-name-or-key-or-path is the name or key or path of the source volume.
name is the name of the new volume. [--prealloc-metadata] preallocate metadata (for
qcow2 images which don't support full allocation). This option creates a sparse image
file with metadata, resulting in higher performance compared to images with no
preallocation and only slightly higher initial disk space usage. When --reflink is
specified, perform a COW lightweight copy, where the data blocks are copied only when
modified. If this is not possible, the copy fails.
vol-delete [--pool pool-or-uuid] vol-name-or-key-or-path [--delete-snapshots]
Delete a given volume. --pool pool-or-uuid is the name or UUID of the storage pool
the volume is in. vol-name-or-key-or-path is the name or key or path of the volume to
delete.
The --delete-snapshots flag specifies that any snapshots associated with the storage
volume should be deleted as well. Not all storage drivers support this option,
presently only rbd.
vol-upload [--pool pool-or-uuid] [--offset bytes] [--length bytes] vol-name-or-key-or-path
local-file
Upload the contents of local-file to a storage volume. --pool pool-or-uuid is the
name or UUID of the storage pool the volume is in. vol-name-or-key-or-path is the
name or key or path of the volume where the file will be uploaded. --offset is the
position in the storage volume at which to start writing the data. The value must be 0
or larger. --length is an upper bound of the amount of data to be uploaded. A negative
value is interpreted as an unsigned long long value to essentially include everything
from the offset to the end of the volume. An error will occur if the local-file is
greater than the specified length. See the description for the libvirt
virStorageVolUpload API for details regarding possible target volume and pool changes
as a result of the pool refresh when the upload is attempted.
vol-download [--pool pool-or-uuid] [--offset bytes] [--length bytes] vol-name-or-key-or-
path local-file
Download the contents of a storage volume to local-file. --pool pool-or-uuid is the
name or UUID of the storage pool the volume is in. vol-name-or-key-or-path is the
name or key or path of the volume to download. --offset is the position in the
storage volume at which to start reading the data. The value must be 0 or larger.
--length is an upper bound of the amount of data to be downloaded. A negative value is
interpreted as an unsigned long long value to essentially include everything from the
offset to the end of the volume.
vol-wipe [--pool pool-or-uuid] [--algorithm algorithm] vol-name-or-key-or-path
Wipe a volume, ensure data previously on the volume is not accessible to future reads.
--pool pool-or-uuid is the name or UUID of the storage pool the volume is in. vol-
name-or-key-or-path is the name or key or path of the volume to wipe. It is possible
to choose different wiping algorithms instead of re-writing volume with zeroes. This
can be done via --algorithm switch.
Supported algorithms
zero - 1-pass all zeroes
nnsa - 4-pass NNSA Policy Letter NAP-14.1-C (XVI-8) for
sanitizing removable and non-removable hard disks:
random x2, 0x00, verify.
dod - 4-pass DoD 5220.22-M section 8-306 procedure for
sanitizing removable and non-removable rigid
disks: random, 0x00, 0xff, verify.
bsi - 9-pass method recommended by the German Center of
Security in Information Technologies
(http://www.bsi.bund.de): 0xff, 0xfe, 0xfd, 0xfb,
0xf7, 0xef, 0xdf, 0xbf, 0x7f.
gutmann - The canonical 35-pass sequence described in
Gutmann's paper.
schneier - 7-pass method described by Bruce Schneier in
"Applied Cryptography" (1996): 0x00, 0xff,
random x5.
pfitzner7 - Roy Pfitzner's 7-random-pass method: random x7.
pfitzner33 - Roy Pfitzner's 33-random-pass method: random x33.
random - 1-pass pattern: random.
Note: The availability of algorithms may be limited by the version of the "scrub"
binary installed on the host.
vol-dumpxml [--pool pool-or-uuid] vol-name-or-key-or-path
Output the volume information as an XML dump to stdout. --pool pool-or-uuid is the
name or UUID of the storage pool the volume is in. vol-name-or-key-or-path is the name
or key or path of the volume to output the XML of.
vol-info [--pool pool-or-uuid] vol-name-or-key-or-path
Returns basic information about the given storage volume. --pool pool-or-uuid is the
name or UUID of the storage pool the volume is in. vol-name-or-key-or-path is the name
or key or path of the volume to return information for.
vol-list [--pool pool-or-uuid] [--details]
Return the list of volumes in the given storage pool. --pool pool-or-uuid is the name
or UUID of the storage pool. The --details option instructs virsh to additionally
display volume type and capacity related information where available.
vol-pool [--uuid] vol-key-or-path
Return the pool name or UUID for a given volume. By default, the pool name is
returned. If the --uuid option is given, the pool UUID is returned instead. vol-key-
or-path is the key or path of the volume to return the pool information for.
vol-path [--pool pool-or-uuid] vol-name-or-key
Return the path for a given volume. --pool pool-or-uuid is the name or UUID of the
storage pool the volume is in. vol-name-or-key is the name or key of the volume to
return the path for.
vol-name vol-key-or-path
Return the name for a given volume. vol-key-or-path is the key or path of the volume
to return the name for.
vol-key [--pool pool-or-uuid] vol-name-or-path
Return the volume key for a given volume. --pool pool-or-uuid is the name or UUID of
the storage pool the volume is in. vol-name-or-path is the name or path of the volume
to return the volume key for.
vol-resize [--pool pool-or-uuid] vol-name-or-path pool-or-uuid capacity [--allocate]
[--delta] [--shrink]
Resize the capacity of the given volume, in bytes. --pool pool-or-uuid is the name or
UUID of the storage pool the volume is in. vol-name-or-key-or-path is the name or key
or path of the volume to resize. The new capacity might be sparse unless --allocate
is specified. Normally, capacity is the new size, but if --delta is present, then it
is added to the existing size. Attempts to shrink the volume will fail unless
--shrink is present; capacity cannot be negative unless --shrink is provided, but a
negative sign is not necessary. capacity is a scaled integer (see NOTES above), which
defaults to bytes if there is no suffix. This command is only safe for storage
volumes not in use by an active guest; see also blockresize for live resizing.
SECRET COMMANDS
The following commands manipulate "secrets" (e.g. passwords, passphrases and encryption
keys). Libvirt can store secrets independently from their use, and other objects (e.g.
volumes or domains) can refer to the secrets for encryption or possibly other uses.
Secrets are identified using a UUID. See <http://libvirt.org/formatsecret.html> for
documentation of the XML format used to represent properties of secrets.
secret-define file
Create a secret with the properties specified in file, with no associated secret
value. If file does not specify a UUID, choose one automatically. If file specifies
a UUID of an existing secret, replace its properties by properties defined in file,
without affecting the secret value.
secret-dumpxml secret
Output properties of secret (specified by its UUID) as an XML dump to stdout.
secret-set-value secret base64
Set the value associated with secret (specified by its UUID) to the value
Base64-encoded value base64.
secret-get-value secret
Output the value associated with secret (specified by its UUID) to stdout, encoded
using Base64.
secret-undefine secret
Delete a secret (specified by its UUID), including the associated value, if any.
secret-list [--ephemeral] [--no-ephemeral] [--private] [--no-private]
Returns the list of secrets. You may also want to filter the returned secrets by
--ephemeral to list the ephemeral ones, --no-ephemeral to list the non-ephemeral ones,
--private to list the private ones, and --no-private to list the non-private ones.
SNAPSHOT COMMANDS
The following commands manipulate domain snapshots. Snapshots take the disk, memory, and
device state of a domain at a point-of-time, and save it for future use. They have many
uses, from saving a "clean" copy of an OS image to saving a domain's state before a
potentially destructive operation. Snapshots are identified with a unique name. See
<http://libvirt.org/formatsnapshot.html> for documentation of the XML format used to
represent properties of snapshots.
snapshot-create domain [xmlfile] {[--redefine [--current]] | [--no-metadata] [--halt]
[--disk-only] [--reuse-external] [--quiesce] [--atomic] [--live]}
Create a snapshot for domain domain with the properties specified in xmlfile.
Normally, the only properties settable for a domain snapshot are the <name> and
<description> elements, as well as <disks> if --disk-only is given; the rest of the
fields are ignored, and automatically filled in by libvirt. If xmlfile is completely
omitted, then libvirt will choose a value for all fields. The new snapshot will
become current, as listed by snapshot-current.
If --halt is specified, the domain will be left in an inactive state after the
snapshot is created.
If --disk-only is specified, the snapshot will only include disk state rather than the
usual system checkpoint with vm state. Disk snapshots are faster than full system
checkpoints, but reverting to a disk snapshot may require fsck or journal replays,
since it is like the disk state at the point when the power cord is abruptly pulled;
and mixing --halt and --disk-only loses any data that was not flushed to disk at the
time.
If --redefine is specified, then all XML elements produced by snapshot-dumpxml are
valid; this can be used to migrate snapshot hierarchy from one machine to another, to
recreate hierarchy for the case of a transient domain that goes away and is later
recreated with the same name and UUID, or to make slight alterations in the snapshot
metadata (such as host-specific aspects of the domain XML embedded in the snapshot).
When this flag is supplied, the xmlfile argument is mandatory, and the domain's
current snapshot will not be altered unless the --current flag is also given.
If --no-metadata is specified, then the snapshot data is created, but any metadata is
immediately discarded (that is, libvirt does not treat the snapshot as current, and
cannot revert to the snapshot unless --redefine is later used to teach libvirt about
the metadata again).
If --reuse-external is specified, and the snapshot XML requests an external snapshot
with a destination of an existing file, then the destination must exist and be pre-
created with correct format and metadata. The file is then reused; otherwise, a
snapshot is refused to avoid losing contents of the existing files.
If --quiesce is specified, libvirt will try to use guest agent to freeze and unfreeze
domain's mounted file systems. However, if domain has no guest agent, snapshot
creation will fail. Currently, this requires --disk-only to be passed as well.
If --atomic is specified, libvirt will guarantee that the snapshot either succeeds, or
fails with no changes; not all hypervisors support this. If this flag is not
specified, then some hypervisors may fail after partially performing the action, and
dumpxml must be used to see whether any partial changes occurred.
If --live is specified, libvirt takes the snapshot while the guest is running. This
increases the size of the memory image of the external checkpoint. This is currently
supported only for external checkpoints.
Existence of snapshot metadata will prevent attempts to undefine a persistent domain.
However, for transient domains, snapshot metadata is silently lost when the domain
quits running (whether by command such as destroy or by internal guest action).
snapshot-create-as domain {[--print-xml] | [--no-metadata] [--halt] [--reuse-external]}
[name] [description] [--disk-only [--quiesce]] [--atomic] [[--live] [--memspec memspec]]
[--diskspec] diskspec]...
Create a snapshot for domain domain with the given <name> and <description>; if either
value is omitted, libvirt will choose a value. If --print-xml is specified, then XML
appropriate for snapshot-create is output, rather than actually creating a snapshot.
Otherwise, if --halt is specified, the domain will be left in an inactive state after
the snapshot is created, and if --disk-only is specified, the snapshot will not
include vm state.
The --memspec option can be used to control whether a checkpoint is internal or
external. The --memspec flag is mandatory, followed by a memspec of the form
[file=]name[,snapshot=type], where type can be no, internal, or external. To include
a literal comma in file=name, escape it with a second comma. --memspec cannot be used
together with --disk-only.
The --diskspec option can be used to control how --disk-only and external checkpoints
create external files. This option can occur multiple times, according to the number
of <disk> elements in the domain xml. Each <diskspec> is in the form
disk[,snapshot=type][,driver=type][,file=name]. A diskspec must be provided for disks
backed by block devices as libvirt doesn't auto-generate file names for those. To
include a literal comma in disk or in file=name, escape it with a second comma. A
literal --diskspec must precede each diskspec unless all three of domain, name, and
description are also present. For example, a diskspec of
"vda,snapshot=external,file=/path/to,,new" results in the following XML:
<disk name='vda' snapshot='external'>
<source file='/path/to,new'/>
</disk>
If --reuse-external is specified, and the domain XML or diskspec option requests an
external snapshot with a destination of an existing file, then the destination must
exist and be pre-created with correct format and metadata. The file is then reused;
otherwise, a snapshot is refused to avoid losing contents of the existing files.
If --quiesce is specified, libvirt will try to use guest agent to freeze and unfreeze
domain's mounted file systems. However, if domain has no guest agent, snapshot
creation will fail. Currently, this requires --disk-only to be passed as well.
If --no-metadata is specified, then the snapshot data is created, but any metadata is
immediately discarded (that is, libvirt does not treat the snapshot as current, and
cannot revert to the snapshot unless snapshot-create is later used to teach libvirt
about the metadata again). This flag is incompatible with --print-xml.
If --atomic is specified, libvirt will guarantee that the snapshot either succeeds, or
fails with no changes; not all hypervisors support this. If this flag is not
specified, then some hypervisors may fail after partially performing the action, and
dumpxml must be used to see whether any partial changes occurred.
If --live is specified, libvirt takes the snapshot while the guest is running. This
increases the size of the memory image of the external checkpoint. This is currently
supported only for external checkpoints.
snapshot-current domain {[--name] | [--security-info] | [snapshotname]}
Without snapshotname, this will output the snapshot XML for the domain's current
snapshot (if any). If --name is specified, just the current snapshot name instead of
the full xml. Otherwise, using --security-info will also include security sensitive
information in the XML.
With snapshotname, this is a request to make the existing named snapshot become the
current snapshot, without reverting the domain.
snapshot-edit domain [snapshotname] [--current] {[--rename] | [--clone]}
Edit the XML configuration file for snapshotname of a domain. If both snapshotname
and --current are specified, also force the edited snapshot to become the current
snapshot. If snapshotname is omitted, then --current must be supplied, to edit the
current snapshot.
This is equivalent to:
virsh snapshot-dumpxml dom name > snapshot.xml
vi snapshot.xml (or make changes with your other text editor)
virsh snapshot-create dom snapshot.xml --redefine [--current]
except that it does some error checking.
The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and
defaults to "vi".
If --rename is specified, then the edits can change the snapshot name. If --clone is
specified, then changing the snapshot name will create a clone of the snapshot
metadata. If neither is specified, then the edits must not change the snapshot name.
Note that changing a snapshot name must be done with care, since the contents of some
snapshots, such as internal snapshots within a single qcow2 file, are accessible only
from the original name.
snapshot-info domain {snapshot | --current}
Output basic information about a named <snapshot>, or the current snapshot with
--current.
snapshot-list domain [--metadata] [--no-metadata] [{--parent | --roots | [{--tree |
--name}]}] [{[--from] snapshot | --current} [--descendants]] [--leaves] [--no-leaves]
[--inactive] [--active] [--disk-only] [--internal] [--external]
List all of the available snapshots for the given domain, defaulting to show columns
for the snapshot name, creation time, and domain state.
If --parent is specified, add a column to the output table giving the name of the
parent of each snapshot. If --roots is specified, the list will be filtered to just
snapshots that have no parents. If --tree is specified, the output will be in a tree
format, listing just snapshot names. These three options are mutually exclusive. If
--name is specified only the snapshot name is printed. This option is mutually
exclusive with --tree.
If --from is provided, filter the list to snapshots which are children of the given
snapshot; or if --current is provided, start at the current snapshot. When used in
isolation or with --parent, the list is limited to direct children unless
--descendants is also present. When used with --tree, the use of --descendants is
implied. This option is not compatible with --roots. Note that the starting point of
--from or --current is not included in the list unless the --tree option is also
present.
If --leaves is specified, the list will be filtered to just snapshots that have no
children. Likewise, if --no-leaves is specified, the list will be filtered to just
snapshots with children. (Note that omitting both options does no filtering, while
providing both options will either produce the same list or error out depending on
whether the server recognizes the flags). Filtering options are not compatible with
--tree.
If --metadata is specified, the list will be filtered to just snapshots that involve
libvirt metadata, and thus would prevent undefine of a persistent domain, or be lost
on destroy of a transient domain. Likewise, if --no-metadata is specified, the list
will be filtered to just snapshots that exist without the need for libvirt metadata.
If --inactive is specified, the list will be filtered to snapshots that were taken
when the domain was shut off. If --active is specified, the list will be filtered to
snapshots that were taken when the domain was running, and where the snapshot includes
the memory state to revert to that running state. If --disk-only is specified, the
list will be filtered to snapshots that were taken when the domain was running, but
where the snapshot includes only disk state.
If --internal is specified, the list will be filtered to snapshots that use internal
storage of existing disk images. If --external is specified, the list will be
filtered to snapshots that use external files for disk images or memory state.
snapshot-dumpxml domain snapshot [--security-info]
Output the snapshot XML for the domain's snapshot named snapshot. Using
--security-info will also include security sensitive information. Use snapshot-
current to easily access the XML of the current snapshot.
snapshot-parent domain {snapshot | --current}
Output the name of the parent snapshot, if any, for the given snapshot, or for the
current snapshot with --current.
snapshot-revert domain {snapshot | --current} [{--running | --paused}] [--force]
Revert the given domain to the snapshot specified by snapshot, or to the current
snapshot with --current. Be aware that this is a destructive action; any changes in
the domain since the last snapshot was taken will be lost. Also note that the state
of the domain after snapshot-revert is complete will be the state of the domain at the
time the original snapshot was taken.
Normally, reverting to a snapshot leaves the domain in the state it was at the time
the snapshot was created, except that a disk snapshot with no vm state leaves the
domain in an inactive state. Passing either the --running or --paused flag will
perform additional state changes (such as booting an inactive domain, or pausing a
running domain). Since transient domains cannot be inactive, it is required to use
one of these flags when reverting to a disk snapshot of a transient domain.
There are two cases where a snapshot revert involves extra risk, which requires the
use of --force to proceed. One is the case of a snapshot that lacks full domain
information for reverting configuration (such as snapshots created prior to libvirt
0.9.5); since libvirt cannot prove that the current configuration matches what was in
use at the time of the snapshot, supplying --force assures libvirt that the snapshot
is compatible with the current configuration (and if it is not, the domain will likely
fail to run). The other is the case of reverting from a running domain to an active
state where a new hypervisor has to be created rather than reusing the existing
hypervisor, because it implies drawbacks such as breaking any existing VNC or Spice
connections; this condition happens with an active snapshot that uses a provably
incompatible configuration, as well as with an inactive snapshot that is combined with
the --start or --pause flag.
snapshot-delete domain {snapshot | --current} [--metadata] [{--children |
--children-only}]
Delete the snapshot for the domain named snapshot, or the current snapshot with
--current. If this snapshot has child snapshots, changes from this snapshot will be
merged into the children. If --children is passed, then delete this snapshot and any
children of this snapshot. If --children-only is passed, then delete any children of
this snapshot, but leave this snapshot intact. These two flags are mutually
exclusive.
If --metadata is specified, then only delete the snapshot metadata maintained by
libvirt, while leaving the snapshot contents intact for access by external tools;
otherwise deleting a snapshot also removes the data contents from that point in time.
NWFILTER COMMANDS
The following commands manipulate network filters. Network filters allow filtering of the
network traffic coming from and going to virtual machines. Individual network traffic
filters are written in XML and may contain references to other network filters, describe
traffic filtering rules, or contain both. Network filters are referenced by virtual
machines from within their interface description. A network filter may be referenced by
multiple virtual machines' interfaces.
nwfilter-define xmlfile
Make a new network filter known to libvirt. If a network filter with the same name
already exists, it will be replaced with the new XML. Any running virtual machine
referencing this network filter will have its network traffic rules adapted. If for
any reason the network traffic filtering rules cannot be instantiated by any of the
running virtual machines, then the new XML will be rejected.
nwfilter-undefine nwfilter-name
Delete a network filter. The deletion will fail if any running virtual machine is
currently using this network filter.
nwfilter-list
List all of the available network filters.
nwfilter-dumpxml nwfilter-name
Output the network filter XML.
nwfilter-edit nwfilter-name
Edit the XML of a network filter.
This is equivalent to:
virsh nwfilter-dumpxml myfilter > myfilter.xml
vi myfilter.xml (or make changes with your other text editor)
virsh nwfilter-define myfilter.xml
except that it does some error checking. The new network filter may be rejected due
to the same reason as mentioned in nwfilter-define.
The editor used can be supplied by the $VISUAL or $EDITOR environment variables, and
defaults to "vi".
HYPERVISOR-SPECIFIC COMMANDS
NOTE: Use of the following commands is strongly discouraged. They can cause libvirt to
become confused and do the wrong thing on subsequent operations. Once you have used these
commands, please do not report problems to the libvirt developers; the reports will be
ignored. If you find that these commands are the only way to accomplish something, then
it is better to request that the feature be added as a first-class citizen in the regular
libvirt library.
qemu-attach pid
Attach an externally launched QEMU process to the libvirt QEMU driver. The QEMU
process must have been created with a monitor connection using the UNIX driver.
Ideally the process will also have had the '-name' argument specified.
$ qemu-kvm -cdrom ~/demo.iso \
-monitor unix:/tmp/demo,server,nowait \
-name foo \
-uuid cece4f9f-dff0-575d-0e8e-01fe380f12ea &
$ QEMUPID=$!
$ virsh qemu-attach $QEMUPID
Not all functions of libvirt are expected to work reliably after attaching to an
externally launched QEMU process. There may be issues with the guest ABI changing upon
migration and device hotplug or hotunplug may not work. The attached environment
should be considered primarily read-only.
qemu-monitor-command domain { [--hmp] | [--pretty] } command...
Send an arbitrary monitor command command to domain domain through the qemu monitor.
The results of the command will be printed on stdout. If --hmp is passed, the command
is considered to be a human monitor command and libvirt will automatically convert it
into QMP if needed. In that case the result will also be converted back from QMP. If
--pretty is given, and the monitor uses QMP, then the output will be pretty-printed.
If more than one argument is provided for command, they are concatenated with a space
in between before passing the single command to the monitor.
qemu-agent-command domain [--timeout seconds | --async | --block] command...
Send an arbitrary guest agent command command to domain domain through qemu agent.
--timeout, --async and --block options are exclusive. --timeout requires timeout
seconds seconds and it must be positive. When --aysnc is given, the command waits for
timeout whether success or failed. And when --block is given, the command waits
forever with blocking timeout.
qemu-monitor-event [domain] [--event event-name] [--loop] [--timeout seconds] [--pretty]
[--regex] [--no-case] [--timestamp]
Wait for arbitrary QEMU monitor events to occur, and print out the details of events
as they happen. The events can optionally be filtered by domain or event-name. The
'query-events' QMP command can be used via qemu-monitor-command to learn what events
are supported. If --regex is used, event-name is a basic regular expression instead
of a literal string. If --no-case is used, event-name will match case-insensitively.
By default, this command is one-shot, and returns success once an event occurs; you
can send SIGINT (usually via "Ctrl-C") to quit immediately. If --timeout is
specified, the command gives up waiting for events after seconds have elapsed. With
--loop, the command prints all events until a timeout or interrupt key. If --pretty
is specified, any JSON event details are pretty-printed for better legibility.
When --timestamp is used, a human-readable timestamp will be printed before the event,
and the timing information provided by QEMU will be omitted.
lxc-enter-namespace domain -- /path/to/binary [arg1, [arg2, ...]]
Enter the namespace of domain and execute the command "/path/to/binary" passing the
requested args. The binary path is relative to the container root filesystem, not the
host root filesystem. The binary will inherit the environment variables / console
visible to virsh. This command only works when connected to the LXC hypervisor driver.
This command succeeds only if "/path/to/binary" has 0 exit status.
ENVIRONMENT
The following environment variables can be set to alter the behaviour of "virsh"
VIRSH_DEBUG=<0 to 4>
Turn on verbose debugging of virsh commands. Valid levels are
· VIRSH_DEBUG=0
DEBUG - Messages at ALL levels get logged
· VIRSH_DEBUG=1
INFO - Logs messages at levels INFO, NOTICE, WARNING and ERROR
· VIRSH_DEBUG=2
NOTICE - Logs messages at levels NOTICE, WARNING and ERROR
· VIRSH_DEBUG=3
WARNING - Logs messages at levels WARNING and ERROR
· VIRSH_DEBUG=4
ERROR - Messages at only ERROR level gets logged.
VIRSH_LOG_FILE="LOGFILE"
The file to log virsh debug messages.
VIRSH_DEFAULT_CONNECT_URI
The hypervisor to connect to by default. Set this to a URI, in the same format as
accepted by the connect option. This environment variable is deprecated in favour of
the global LIBVIRT_DEFAULT_URI variable which serves the same purpose.
LIBVIRT_DEFAULT_URI
The hypervisor to connect to by default. Set this to a URI, in the same format as
accepted by the connect option. This overrides the default URI set in any client
config file and prevents libvirt from probing for drivers.
VISUAL
The editor to use by the edit and related options.
EDITOR
The editor to use by the edit and related options, if "VISUAL" is not set.
VIRSH_HISTSIZE
The number of commands to remember in the command history. The default value is 500.
LIBVIRT_DEBUG=LEVEL
Turn on verbose debugging of all libvirt API calls. Valid levels are
· LIBVIRT_DEBUG=1
Messages at level DEBUG or above
· LIBVIRT_DEBUG=2
Messages at level INFO or above
· LIBVIRT_DEBUG=3
Messages at level WARNING or above
· LIBVIRT_DEBUG=4
Messages at level ERROR or above
For further information about debugging options consult
"http://libvirt.org/logging.html"
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