sit0 device and SNMP

[Fernando Gozalo]

> b r u ma wrote:
>> hi,
>>
>> This is question for Fedora 1, not sure if this is right list, but any
>> way ...
>>
>> When I run
>> $ snmpwalk -v 1 -c public localhost ifDescr
>>
>> i get this:
>> IF-MIB::ifDescr.1 = STRING: lo
>> IF-MIB::ifDescr.2 = STRING: eth0
>> IF-MIB::ifDescr.3 = STRING: eth1
>> IF-MIB::ifDescr.4 = STRING: eth2
>> IF-MIB::ifDescr.5 = STRING: ppp0
>> IF-MIB::ifDescr.6 = STRING: sit0
>>
>> but sometimes after reboot, ppp0 and sit0 device change order:
>> ...
>> IF-MIB::ifDescr.4 = STRING: eth2
>> IF-MIB::ifDescr.5 = STRING: sit0
>> IF-MIB::ifDescr.6 = STRING: ppp0
>>
>> I use SNMP to monitor traffic (MRTG) on ppp0, because of this switching,
>> I'm sometimes monitoring wrong data...
>>
>> Strange thing is that I never used sit0 device, also $ifconfig don't
>> list it, so why is there? How do I remove it, or make it fixed?
>>
>> regards bruma
>>
>
> I've talked a little with the net-snmp folks and if you look at the
> mailinglist of the net-snmp-coders-list they are working on fixing this
> ordering.
>
> Don't forget though that adding new devices during the runtime of your
> system can lead to these kinds of changes, no matter what.
>
> Read ya, Phil
>
> PS: And yes, i agree, it's very annoying that it does this, but imho
> MRTG would just need to be a little more intelligent and one should be
> able to specify a device name instead of a index number for monitoring.
> So one could argue that it's actually a (design) bug in MRTG.

You can config MRTG to query using the IP configured in the interface
instead of the index of the interface. See MRTG config manual.

Un saludo.
Fernando.