This article describes how Master/Slave election is done in Cluster member mode of FortiAuthenticator.
Scope
FortiAuthenticator.
Solution
1) if the uptime difference is less than 5Mins High priority FortiAuthenticator will become Master.
2) If the uptime difference is more than 5 Mins
longest Uptime FortiAuthenticator will become Master.
Note.
When the FortiAuthenticator HA Cluster mode is updated and the FortiAuthenticator uptime diff is more than 5 Mins after the upgrade, longest Uptime FortiAuthenticator will become Master and that is the reason why HA master changes after firmware upgrade without not following the HA priority.
