We have recently deployed a few Nexus 5596s running NX-OS 5.1(3)N1(1a). We have been using a UnDP poller OLD-CISCO-SYS-MIB:whyReload OID 126.96.36.199.188.8.131.52.1.2 which works for all Cisco devices except ASAs. This no longer works for the Nexus OS. UnDP returns 'OID not supported'. Does anyone know if this is a bug, Cisco moved this object or it is no longer supported in the NX-OS?
If a get next request isn't returning data, then I'd suspect that the MIB is no longer supported by the OS on the Nexus. You can verify by running the snmpwalk.exe in the NPM install directory and configuring that specific OID. The text output will let you know if the MIB is supported or not.
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