How To: Use MRTG with GNS3

What is MRTG?

• MRTG is opensource program which gets traffic statistics from devices using SNMP and builds graphs like this:

Installing MRTG

• Download MRTG from http://oss.oetiker.ch/mrtg/ and follow installing instructions to install MRTG

Setup virtual topology

In this case we wan’t to make most simple example so we are using only one router:

•  Install Ms loopback adapter to your Windows machine and configured IP-address 10.10.10.1/24 for it.

• Configure router:

hostname R0

!

interface FastEthernet1/0

ip address 10.10.10.2 255.255.255.0

duplex auto

speed auto

!

!

!

snmp-server community mycommunity RO

Verify that ping goes from your local computer to emulated router R0

Configure and run MRTG

• Follow MRTG guide: http://oss.oetiker.ch/mrtg/doc/mrtg-nt-guide.en.html

• After you have configured MRTG with command:

perl cfgmaker mycommunity@10.10.10.2 –global “WorkDir: c:\www\mrtg” –output mrtg.cfg

• Run MRTG with command:

perl mrtg mrtg.cfg

Every time when you run MRTG it will get data from the router and save it. You can run MRTG manually every 5 minutes or configure this to happen automatically. To do this follow MRTGinstructions. When you have done this MRTG starts to build graph for you.