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[LINUX] Interface index traffic




First, sorry for my english :p

I use PRTG to monitor network devices (router running on Debian Linux).
I monitor the network interfaces without problems.
But if an interface goes from one state UP to DOWN then UP then I have a problem with indexes (interface is No such NAME SNMP error).

The interfaces are configured as follow:
- display alarm if disconnected
- snmp v2c
- 64bit counter (i tried 32 bit but unsuccesfull)
- multi-get use
- Port name: (Alias​​: [ifalias]) (Port: [port])
- automatic update if name changes in the device
- use ifAlias

is there a way to "fix" the indexes on Linux? Any solution ?

Thank you.

index interface linux

Created on Apr 13, 2012 12:03:01 PM

Last change on Apr 13, 2012 12:34:12 PM by  Konstantin Wolff [Paessler Support]

7 Replies



Hi, what NET-SNMP version are you using? I just tried to recreate the issue you have but I was not successful...
Addtional I'm afraid the RFCs do not require the ifIndex persistant.
The requirement for constancy (between re-initializations) of an interface's ifIndex value is met by requiring that after an interface is dynamically removed, its ifIndex value is not re-used by a different dynamically added interface until after the following re-initialization of the network management system.
------ (quote from RFC 2863)
But as mentioned above, I'm not facing these issues with the following version of NET-SNMP (5.4.3dfsg-2.2ubuntu1).
Best regards

Created on Apr 13, 2012 12:45:07 PM by  Konstantin Wolff [Paessler Support]



NET-SNMP version: 5.4.1

the problem is only with linux device, no problem with CISCO (re-index is OK)

Created on Apr 13, 2012 12:54:15 PM



just an info, my problem appears only for ppp (adsl) and nas (sdsl) interfaces no problem for interfaces like ETH1,ETH0..etc..

Created on Apr 13, 2012 2:34:22 PM



Sorry, my problem is only with PPP interfaces....

Created on Apr 16, 2012 6:47:16 AM



any idea ?

Created on Apr 16, 2012 12:33:06 PM



I'm afraid we do not have a solution for that and I'm not quite sure if there is a solution at all. Sorry.
Maybe a other user knows more about that. Best regards

Created on Apr 16, 2012 1:23:36 PM by  Konstantin Wolff [Paessler Support]




I have a same problem, =)

network up and down, then up, I have problem.


  1. snmpwalk -v2c -cxxx localhost | grep ifIndex IF-MIB::ifIndex.1 = INTEGER: 1 (lo) IF-MIB::ifIndex.2 = INTEGER: 2 (eth0) IF-MIB::ifIndex.3 = INTEGER: 3 (eth1) IF-MIB::ifIndex.6 = INTEGER: 6 (bond0) <-- increase count +1

that's is problem,

I'm using OpenSuse 11.4. do you know how to change from ifIndex.6 to ifIndex.1 ??

regard, thanks

Created on Apr 19, 2012 8:49:27 AM

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