Exclude SNMP OIDs from being polled by DNAC

[Sylvain_Che]

Hello,

By default DNAC polls a network device via SNMP every 10 minutes on many OIDs.

For low-end or legacy switches running old IOS version (C3650 - IOS-XE 3.6.8E for example), I see SNMP CPUHOG on a few specific OIDs. These CPU spikes lead to some traffic disruption (STP BPDUs not generated/processed for example). Obviously, the long-term solution would be to upgrade SW/HW.

For a short-term solution, from switch config, we can exclude the specific OIDs to be polled. This solution is OK.

However I'm wondering if we can configure DNAC to not poll these specific OIDs globally? And based on certain criteria (ex: if device=3650, then don't poll these OIDs)?

Regards,

Sylvain.

[Preston Chilcote · Accepted solution]

The default network resync interval is 24 hours.  Outside of that, I think the SNMP polling is limited to DNA asynchronously responding to certain SNMP traps sent from the device.  For example, if an interface flaps, and the switch sends a trap to DNA, then DNA will use SNMP to collect some additional info in case it needs to report an issue.

So, you may have some other issue that is the real root cause here.  Firstly though, I expect the CPUHOGS are actually a software bug, not related to amount of polling.  The minimum compatible release for 3650 is IOS XE 16.6.3, so I suggest a software upgrade.