Priority Group Activation in F5 allows configuring the standby server(s) for the active server(s) in the pool.
Standby server(s) won’t receive the traffic from the F5 until primary servers are running.
Standby server(s) are automatically activated once the defined number of primary servers goes down.
Priority Group Activation feature mainly used to provide a web page with maintenance to the clients when the number of primary server(s) was unavailable due to load.
Priority Group Activation allows you to configure multiple priority groups within the pool.
If Priority Group Activation is set then F5 LTM will use available members with the highest priority number first.
