To enable group mode, create a group of two or more appliances. An appliance can be a member of only one group. Group members are identified by IP address and the SSL common name in the appliance license.
All group mode parameters are on the Settings: Group Mode page, in the Configure Settings: Group Mode table.
To enable group mode
If the other group member is a high-availability pair, specify the SSL Common Name of the HA secondary appliance in the HA Secondary SSL Common Name column.