We have "N9K-C93120TX" switch in Cisco ACI Cluster. The monitoring tool is not fetching the correct Slno and Sysname from the device at same time we have observed the SNMP Walk is fine towards this device.
1) Configure an out-of-band contract allowing SNMP traffic. SNMP traffic typically uses UDP port 161 for SNMP requests.
2) Configure the APIC out-of-band IP addresses in the 'mgmt' tenant. Although the out-of-band addresses are configured during APIC setup, the addresses must be explicitly configured in the 'mgmt' tenant before the out-of-band contract will take effect.