Technical Tip: SNMP v3 connection timing out in a FortiGate running 7.6.0

When a user attempts to make a query towards a FortiGate HA cluster using SNMP v3 in 7.6.0, the timeout issue can occur, as in the example below, receiving a message: 'timeout: no response from fortigate_ip':

However, the same query in FortiOS 7.4 works properly as below:

This query is done towards the HA management interface, and ha-direct is enabled; however, both units cannot be queried in 7.6.0. The FortiGate HA and SNMP have a simple configuration as below:

HA configuration:

config system ha

    set group-name "AzureHA"

    set mode a-p

    set hbdev "port3" 100

    set session-pickup enable

    set session-pickup-connectionless enable

    set ha-mgmt-status enable

        config ha-mgmt-interfaces

            edit 1

                set interface "port4"

                set gateway 172.16.64.193

            next

        end

    set override disable

    set priority 1

    set unicast-hb enable

    set unicast-hb-peerip 172.16.64.132

end

SNMP configuration:

config system snmp user

    edit "Alan"

        set notify-hosts ip_querier

        set ha-direct enable

        set security-level auth-no-priv

        set auth-proto sha256

        set auth-pwd password

    next

end

SNMP enabled in the port4, HA-management interface:

config system interface

Workarounds:

1. Downgrade to 7.4.5, as the issue was acknowledged by the R&D team and it is only happening in the 7.6.0 version.
2. Upgrade to 7.6.1 when it is released, as the fix will be implemented in this version.
3. Use SNMP v2 or v1 instead.