sit0 device and SNMP

[Phil Knirsch]

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.

-- 
Philipp Knirsch      | Tel.:  +49-711-96437-470
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