Redundancy state change conditions?

What are the conditions triggering the change of the BACKUP GW from warm mode to active mode
and the MASTER GW from active to …?

Are some GW state like CPU load or particular thread activity or internal DB monitored ?

Could you shrae a statechart diagram explaining the possible state and transition ?

IIRC a backup becomes active when there is a loss of communication between the backup and the master (normally caused by the master Gateway stopping for whatever reason). When communication is re-established between the master and backup, the master sends a signal to the backup to become inactive. Starting in 7.7, you can also manually force a master to become inactive and a backup to become active (and vice versa).