Troubleshooting Tip: FortiAuthenticator Load Balancer Active-Active is not working during a failover

Not all settings are synchronized when Load Balancer Active-Active is deployed.

So any basic required settings for each node need to be properly configured first.

Troubleshooting tools:

1. Packet capture, to see if there's actually an incoming authentication request into the Secondary node.
2. FortiAuthenticator debug page to check the HA sync and authentication process:

https://<FortiAuthenticator IP Address>/debug/ 

Things that may be worth checking:

1. Interface feature setting: Network -> Interface -> Select the Interface name -> Services options.
2. Remote Authentication Server.
   If required, both nodes need to join the same Active Directory domain.
3. Shared key for the RADIUS Client.

Make sure both nodes' keys are the same as what is configured on the RADIUS Client.

Related article:

Technical Tip: How to configure FortiAuthenticator load-balancing cluster