MIB Value change after Router reboot

[Pankaj Raj]

Hi friends,

I have faced one issue in my network in recent times. When any router reboots (Hard/Soft restart), it's MIB Value changes. Although it happens very less (very few times). Mostly, MIB value remains same I guess, but only some times it gets changed itself.

I monitor the routers & few of its interfaces using SNMP. The MIB Value is taken from the SNMPWALK command whose sample output is shared below.

snmpwalk -v 2c -c public X.X.X.X

[OUTPUT CUT]

IF-MIB::ifDescr.1 = STRING: FastEthernet0/0
IF-MIB::ifDescr.2 = STRING: Serial0/0
IF-MIB::ifDescr.3 = STRING: FastEthernet0/1
IF-MIB::ifDescr.4 = STRING: Serial0/1
IF-MIB::ifDescr.5 = STRING: Serial0/2
IF-MIB::ifDescr.6 = STRING: Serial0/3

[OUTPUT CUT]

For Example: If I have to monitor interface Serial0/1, I integrate the MIB Value "4" in monitoring tool. But, sometimes, when router restarts, the value (Number 4) of this interface changes itself & hence monitoring tool gives incorrect data as that number belongs to any other interface or nowhere after restart.

Can anyone plz help me out, what to do in such scenario?

Thanks in advance..

[Andreas Martensson · Accepted solution]

Hi,

Check out the following command;

"snmp-server ifindex persist"

/Andreas

[Pankaj Raj]

Hi Andreas,

Thanks for the command. I read about this command & found that if this command is configured, router will retain the same/previous MIB value if it restarts i.e. the IfIndex value will be fixed for all interfaces.

Thanks for the helpful support.. :)