mrtg - Online in the Cloud

PROGRAM:

NAME

mrtg - What is MRTG ?

DESCRIPTION

The Multi Router Traffic Grapher (MRTG) is a tool to monitor the traffic load on network
links. MRTG generates HTML pages containing PNG images which provide a LIVE visual
representation of this traffic. Check http://www.stat.ee.ethz.ch/mrtg/ to see what it
does.

Go to
http://oss.oetiker.ch/mrtg for all the details about mrtg.

HIGHLIGHTS

Portable
MRTG works on most UNIX platforms and Windows NT.

Perl
MRTG is written in Perl and comes with full source.

Portable SNMP
MRTG Uses a highly portable SNMP implementation written entirely in Perl (thanks to
Simon Leinen). There is no need to install any external SNMP package.

SNMPv2c support
MRTG can read the new SNMPv2c 64bit counters. No more counter wrapping.

Reliable Interface Identification
Router interfaces can be identified by IP address, description and ethernet address in
addition to the normal interface number.

Constant size Logfiles
MRTG's logfiles do NOT grow thanks to the use of a unique data consolidation
algorithm.

Automatic Configuration
MRTG comes with a set of configuration tools which make configuration and setup very
simple.

Performance
Time critical routines are written in C (thanks to the initiative of Dave Rand my Co-
Author).

GIF free Graphics
Graphics are generated directly in PNG format using the GD library by Thomas Boutell.

Customizability
The look of the webpages produced by MRTG is highly configurable.

RRDtool
MRTG has built-in hooks for using RRDtool. If you are strapped for performance this
may help.

DETAILS

MRTG consists of a Perl script which uses SNMP to read the traffic counters of your
routers and a fast C program which logs the traffic data and creates beautiful graphs
representing the traffic on the monitored network connection. These graphs are embedded
into webpages which can be viewed from any modern Web-browser.

In addition to a detailed daily view, MRTG also creates visual representations of the
traffic seen during the last seven days, the last five weeks and the last twelve months.
This is possible because MRTG keeps a log of all the data it has pulled from the router.
This log is automatically consolidated so that it does not grow over time, but still
contains all the relevant data for all the traffic seen over the last two years. This is
all performed in an efficient manner. Therefore you can monitor 200 or more network links
from any halfway decent UNIX box.

MRTG is not limited to monitoring traffic, though. It is possible to monitor any SNMP
variable you choose. You can even use an external program to gather the data which should
be monitored via MRTG. People are using MRTG, to monitor things such as System Load, Login
Sessions, Modem availability and more. MRTG even allows you to accumulate two or more data
sources into a single graph.

HISTORY

In 1994 I was working at a site where we had one 64kbit line to the outside world.
Obviously, everybody was interested in knowing how the link was performing. So I wrote a
quick hack which created a constantly updated graph on the web that showed the traffic
load on our Internet link. This eventually evolved into a rather configurable Perl script
called MRTG-1.0 which I released in spring 1995. After a few updates, I left my job at DMU
to start work at the Swiss Federal Institute of Technology. Due to lack of time I had to
put MRTG aside. One day in January of 1996, I received email from Dave Rand asking if I
had any ideas why MRTG was so slow. Actually, I did. MRTG's programming was not very
efficient and it was written entirely in Perl. After a week or so, Dave wrote back to me
and said he had tried what I had suggested for improving MRTG's speed. Since the changes
did not help much, he had decided to rewrite the time-critical sections of MRTG in C. The
code was attached to his email. His tool increased the speed of MRTG by a factor of 40!
This got me out of my 'MRTG ignorance' and I started to spend my spare time developing of
MRTG-2.

Soon after MRTG-2 development had begun I started to give beta copies to interested
parties. In return I got many feature patches, a lot of user feedback and bug fixes. The
product you are getting now wouldn't be in this state if it hadn't been for the great
contributions and support I received from of many people. I would like to take this
opportunity to thank them all. (See the files CHANGES for a long list of folk people who
helped to make MRTG what it is today.)

Command-line

Mrtg is also the name of the script you have to run to poll data and generate the graphs.
Most configuration is set through the configuration file; some command-line options exist
all the same.

--user username and --group groupname
Run as the given user and/or group. (Unix Only)

--lock-file filename
Use an alternate lock-file (the default is to use the configuration-file appended with
"_l").

--confcache-file filename
Use an alternate confcache-file (the default is to use the configuration-file appended
with ".ok")

--logging filename|eventlog
If this is set to writable filename, all output from mrtg (warnings, debug messages,
errors) will go to filename. If you are running on Win32 you can specify eventlog
instead of a filename which will send all error to the windows event log.

NOTE:Note, there is no Message DLL for mrtg. This has the side effect that the windows
event logger will display a nice message with every entry in the event log, complaing
about the fact that mrtg has no message dll. If any of the Windows folks want to
contribute one, they are welcome.

--daemon
Put MRTG into the background, running as a daemon. This works the same way as the
config file option, but the switch is required for proper FHS operation (because
/var/run is writable only by root)

--fhs
Configure all mrtg paths to conform to the FHS specification;
http://www.pathname.com/fhs/

--check
Only check the cfg file for errors. Do not do anything.

--pid-file=s
Define the name and path of the pid file for mrtg running as a daemon

--log-only
Only update the logfile, do not produce graphics or html pages

--debug=s
Enable debug options. The argument of the debug option is a comma separated list of
debug values:

cfg - watch the config file reading
dir - directory mangeling
base - basic program flow
tarp - target parser
snpo - snmp polling
fork - forking view
time - some timing info
log - logging of data via rateup or rrdtool

Example:

--debug="cfg,snpo"

READ ON

Learn more about MRTG by going to the mrtg home page on: http://oss.oetiker.ch/mrtg

Use mrtg online using onworks.net services