3 Replies Latest reply on Dec 16, 2015 10:07 AM by pratikmehta003

    SNMP Information Doesn't Match Device Configuration For Interface

    Larry Giveans

      So I have a router, Cisco model 2821, that I would swear was showing an interface yesterday that is no longer available. For the sake of discussion let's call the interface 'Tunnel1000'.  There are a number of interfaces of various types visible on this device and it's returning other information such as hardware health, etc. without a hiccup.  But while 8 or so other interfaces are present my Tunnel1000 isn't.

       

      The network admin has shown me in many different ways that the port I'm looking for is indeed present.  I can see it in device config and he's pinged to and from other devices connected via this port.  In doing an SNMP walk however I see all of the interfaces listed in Orion in the .1.3.6.1.2.1.2.2.1.2. range (where I believe the ports are pulled from) but no sign of the T1000 interface.  The only place I see references to the T1000 port are in the .1.3.6.1.4.1.9.9.172.1.2.1.1.2.1367 OID range and the string returned isn't exactly what I'm looking for... STRING: "Tunnel1000-head-0"  No other interface name contains 'T1000' so I'm thinking this is perhaps a clue.

       

      Another piece of information is that the network admin added a new interface yesterday, Tunnel3000.  This interface shows up fine.  And finally I do see one interface with a 'Null0' caption... perhaps my Tunnel1000? 1.3.6.1.2.1.2.2.1.2.5 = STRING: "Null0"

       

      So the root of the problem seems to be that the SNMP information being returned by the devices doesn't match the current device configuration.   I've done numerous SNMP walks and have scanned them multiple times looking for my interface.  And as I mentioned at the beginning I'm almost positive it was present prior to the device config mods yesterday.  So unless I'm missing something this information is out of sync - any ideas of how to force SNMP to update on the device?  Am I missing something, what else can I look at?

       

      Missing Interface.PNG