We currently have a pair of Cisco ASA 5510 firewalls in an active/standby failover configuration. They are currently running 7.0(6) and we'd like to upgrade them to 8.2.4. Is it possible to failover to one of them while we upgrade the other and failover again to upgrade the other one? Also, is there anything that we should watch out for when upgrading from 7.0(6) to 8.2.4? I read that we should upgrade to 7.1, then 7.2, and then 8.2.