Troubleshooting Tip: Resolving the 'HTTP Success' error when registering a FortiGate HA Cluster to FortiCare using a Logical Serial Number

On a FortiGate HA cluster using a logical serial number, if licenses appear as invalid, attempting to register the device to FortiCare via FortiGuard -> Login to FortiCare may trigger the ‘HTTP Success’ error, as shown below:

To solve this issue, execute the following commands on both FortiGate firewalls and then reboot each of them one by one:

    config system ha
        set logical-sn enable
    end

Note:
vSN support was introduced in FortiOS versions 7.2.9, 7.4.6, and 7.6.1. Devices running versions earlier than these will encounter the same error. Upgrade devices to supported version in that case to fix the issue.

FortiGate 100F and 101F models may encounter the error 'No valid cluster key as logical-sn is enabled', or may not have the 'logical-sn enable' option available in the CLI. For more information, see Technical Tip: Logical Serial Number feature not working on FortiGate-100F/101F.

Related documents:

Generating an HA cluster | Fortinet Document Library

Single FortiGuard license for FortiGate A-P HA cluster | Fortinet Document Library