Primary will be always primary and secondary will be always secondary.., only you can change the Active and standby mode. after putting "failover active" on standby unit, it will become Secondary/Active and other will be primary/Standby. Regards,Saur...

I am also planning to upgrade my ASA 5520 to Firepower appliance. Can anyone please assist if we can create sub interfaces on FIrePOWER ?my firewall has many sub interfaces under FE0/1.Will tool automatically convert the ASA configuration to FTD comp...