Troubleshooting Tip: SNMP error 'No Such Instance currently exists at this OID'

[subramanis]

Description	This article describes the explanation for the error 'No Such Instance currently exists at this OID' that appears when performing an snmpwalk.
Scope	FortiGate.
Solution	This error appears when performing the snmpwalk from the linux machine or any other operating systems. Example: Name: fgIntfVlanHbCount OID: 1.3.6.1.4.1.12356.101.7.4.1 Description: The number of entries in fgIntfVlanHbTable. The snmpwalk returns the INTEGER:0 when querying the fgIntfVlanHbCount: snmpwalk -v2c -c Forti 10.191.20.44 1.3.6.1.4.1.12356.101.7.4.1 iso.3.6.1.4.1.12356.101.7.4.1.0 = INTEGER: 0 When querying the leaf OID fgIntfVlanHbTable, no data will be returned because the branch OID count INTEGER = 0, indicating that there is no IntfVlanHb data on the device. Name: fgIntfVlanHbTable Oid: 1.3.6.1.4.1.12356.101.7.4.2 Description: A list of VlanHbs and values. snmpwalk -v2c -c Forti 10.191.20.44 1.3.6.1.4.1.12356.101.7.4.2 iso.3.6.1.4.1.12356.101.7.4.2 = No Such Object available on this agent at this OID The error is expected and occurs as part of normal operation. To ensure the intended OID exists, execute the snmpwalk command to walk through the OID branch by polling the OID located directly above the original one. snmpwalk -v2c -c Forti 10.191.20.44 1.3.6.1.4.1.12356.101.7.4 iso.3.6.1.4.1.12356.101.7.4.1.0 = INTEGER: 0 The branch 1.3.6.1.4.1.12356.101.7.4 will return all relevant data for the leaf OIDs, including 10.191.20.44 1.3.6.1.4.1.12356.101.7.4.1 and 10.191.20.44 1.3.6.1.4.1.12356.101.7.4.2.1, and so on. It was possible to analyze the branch and leaf OIDs through the ireasoning MIB Browser: