Technical Tip: How to monitor HA cluster members individually through Public Interface using SNMPv3

Description

This article describes how to individually monitor HA cluster members, which are only accessible to the SNMP server through the external interface. In this scenario, ha-direct cannot be used on the cluster members.

Scope

FortiGate.

Solution

Starting from v7.6.0, snmpd supports querying the Secondary cluster member from the Primary FortiGate by adding the Secondary member's Serial Number after the username in the snmpwalk command, as shown below:

snmpwalk -v3 -l noAuthNoPriv -u username-FortiGate_Serial_Number Host_IP OID

Note:
For snmpv3 it is required that the Primary and Secondary cluster members have the same engine-id configured within config.system.snmp.sysinfo. See the below KB article for reference: Technical Tip: SNMP V3 trap configuration with FortiGate running HA

Related articles:
Technical Tip: SNMP communication working scenario with respect to FortiGate device in HA and ha-direct options
Technical Tip: OIDs for monitoring HA
Technical Tip: Setup FortiGate HA failover alert on SNMP managers (OID)