C9200 - SNMP traps including interface description

[Ethan-H]

Hi, 

we have replaced several C2960 and C3560 with new C9200L switches running on IOS XE 17.9.5. I would like to have the switches to send out SNMP traps (preferable v3, but I would even be happy with v1/v2c) on interface status changes including the interface description (alias) - which is not working.

I've tried all possible SNMP trap version commands, I've tried it with or without "snmp-server traps link ietf". The switch just won't be sending out the interface traps including the interface alias/description.

This is the whole SNMP trap message the switch sends out:

IF-MIB:linkDown : ifIndex.27 = 27, ifAdminStatus.27 = 1, ifOperStatus.27 = 2, ifDescr.27 = TenGigabitEthernet1/0/19, ifType.27 = 6, locIfReason.27 = down, sysUpTime = 18 days 1 hour 52 minutes 42,44 seconds, experimental.1057.1.0 = XXXX, snmpTrapEnterprise = SNMPv2-MIB:snmpTraps

For comparison, here's a trap from another new Cisco Nexus 9300 switch we have installed recently - this is what I would like to receive from the IOS switch too:

IF-MIB:linkUp : ifIndex.436214272 = 436214272, ifAdminStatus.436214272 = 1, ifOperStatus.436214272 = 1, ifDescr.436214272 = Ethernet1/14, ifAlias.436214272 = TEST-Server:10ge1, sysUpTime = 31 days 22 hours 58 minutes 30,48 seconds, experimental.1057.1.0 = XXXX, snmpTrapEnterprise = SNMPv2-MIB:snmpTraps

And yes, I know that I can poll the devices (what I am also doing of course), but I would like to have it sending out traps

Thanks,

E.

[Ethan-H]

Hi, 

thanks for your reply. The SNMP config is correct, traps have been enabled of course on the switches and they are being sent out (and received) correctly.

As already mentioned and as you can see in the example above, the problem is that the received link status change traps do not include the interface alias ("switchport description"), only the interface name (e.g. "Eth1/14").

I am not aware of any SNMP trap limitations on the latest Catalyst switches (IOS XE 17.9.5). 

But what do you mean with: "Confirm that the necessary SNMP MIBs are supported and loaded on the switches" ? The switches are running the default configuration / MIBS from the official Cisco software image (IOS XE 17.9.5). What else could or should we activate for sending out SNMP traps?

Thanks & regards,
Ethan

[balaji.bandi]

This is interesting question. Ss in theory your IOS and nexus working, 

On cat 9200 IOS XE running that is not working - if you do  SNMP walk - are you able to get that information for testing ?

If you not able to get that information , then that can be limitation or some bug.

check also messages :

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/17_xe/syslogs/17-13-x/b-system-message-guide-17-13-x.html

[Ethan-H]

Polling the switch interfaces is working fine, I can get the interface aliases/switchport descriptions as expected.

BTW: I see the same behavior on our 9500-40X Catalyst Switches also running on IOS XE 17.9.5 => traps are being sent out correctly, but the SNMP trap message on link status change doesn't include the "interface alias".

I was just wondering: are we the only one's using snmp trap notification including the interface aliases on these switches?

[Niklas.D]

Did anyone get this to work? 

[Ethan-H]

Hi,

actually, NO. Obviously, Cisco isn't interested in changing or improving this behaviour for IOS. I don't really know why, because it would be an easy and very helpful change, but what I've heard was only "works as designed". Only Cisco knows why NXOS can do it, but IOS not...

Therefore, the workaround for our NMS is: once we receive an SNMP trap from an IOS device, we extract the interface number and perform another lookup within our database to get the corresponding interface alias. We then use both information in our e-mail notification. 

It would still be great if Cisco could do this out of the box, though!

[Niklas.D]

I see this is very strange, becuse i got it to work yesterday on a old 2960-X Switch

and today its not working,,,