Our CIMC is configured for snmp v2 for RO (limited).
If I poll from another source, I must specify the OID start as .1 to get any information:
Without an OID start (normal snmp query):
$ snmpwalk -v 2c -c ********* hostname-cimc
SNMPv2-SMI::mib-2 = No Such Object available on this agent at this OID
Adding the OID generic start of .1:
$ snmpwalk -v 2c -c ********* hostname-cimc
SNMPv2-SMI::enterprises.9.9.719.1.9.6.1.2.1 = STRING: "sys/rack-unit-1/board"
SNMPv2-SMI::enterprises.9.9.719.1.9.6.1.3.1 = STRING: "board"
SNMPv2-SMI::enterprises.9.9.719.1.9.6.1.4.1 = INTEGER: 100
SNMPv2-SMI::enterprises.9.9.719.1.9.6.1.5.1 = Gauge32: 1
SNMPv2-SMI::enterprises.9.9.719.1.9.6.1.6.1 = STRING: "UCSC-C460-M4"
...
SNMPv2-SMI::enterprises.9.9.719.1.9.6.1.16.1 = STRING: "Cisco Systems Inc"
...
SNMPv2-SMI::enterprises.9.9.719.1.9.35.1.9.1 = Gauge32: 3145728
...
SNMPv2-SMI::enterprises.9.9.719.1.9.35.1.51.1 = STRING: "Cisco Systems Inc"
...
SNMPv2-SMI::enterprises.9.9.719.1.9.35.1.55.1 = Gauge32: 1333
SNMPv2-SMI::enterprises.9.9.719.1.9.35.1.56.1 = ""
SNMPv2-SMI::enterprises.9.9.719.1.9.35.1.56.1 = No more variables left in this MIB View (It is past the end of the MIB tree)
About 100 lines in all.
So, SNMP 'works,' but when I then go to SW NPM to actually add the CIMC as a 'node,' and enter the proper credentials, I get 'Test Failed.' (see image).

Now, the 'UCS Credential Section' lower on the page does work, and is confirmed....but the SNMP portion is not...Here is why that is an issue...
When I finally complete the 'add node,' I basically just get ICMP live stats, and nothing from the UCS itself.