MRTG and network interfaces

I tend to restart OpenVPN a lot due to config changes. As a result, this brings quite some issues to MRTG (or more precisely, SNMP), due to the fact tun devices change of ID.

A while back, I found a quick fix for this; rename the interface targets from their respective ID to their name:

Target[eth0]: 2:public@localhost


Target[eth0]: #eth0:public@localhost
For example:
# Eth0 stats
Options[eth0]: growright, nobanner, pngdate, nopercent, noinfo
Target[eth0]: #eth0:public@localhost:
SetEnv[eth0]: MRTG_INT_DESCR="eth0"
MaxBytes[eth0]: 1250000
Title[eth0]: Traffic Analysis for deng
PageTop[eth0]: <H1>Traffic Analysis for deng (eth0)</H1>
# Eth1 stats
Options[eth1]: growright, nobanner, pngdate, nopercent, noinfo
Target[eth1]: #eth1:public@localhost:
SetEnv[eth1]: MRTG_INT_DESCR="eth1"
MaxBytes[eth1]: 1250000
Title[eth1]: Traffic Analysis for deng
PageTop[eth1]: <H1>Traffic Analysis for deng (eth1)</H1>
# tun0 stats
Options[tun0]: growright, nobanner, pngdate, nopercent, noinfo
Target[tun0]: #tun0:public@localhost:
SetEnv[tun0]: MRTG_INT_DESCR="tun0"
MaxBytes[tun0]: 1250000
Title[tun0]: Traffic Analysis for deng
PageTop[tun0]: <H1>Traffic Analysis for deng (tun0)</H1>

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2 responses to “MRTG and network interfaces”

  1. Peter avatar

    Good info except shouldn’t the hash character in the target be replaced by ‘\’ ?

  2. Yeri Tiete avatar

    # should work. At least in 2011.
    It’s been a while since I’ve played with MRTG.

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