以下的步驟非常的清楚明瞭
- Download the new OS image into the primary firewall
- Save the running configuration on the primary unit
- Power off the primary unit and remove its network connections
- Restore power to the primary unit
- Verify that the new operating system release is loaded and that it appears to run correctly
- Power the primary unit off again and reconnect its interface connections.
- Download the new OS image into the secondary unit
- Power off the secondary unit and restore power to the primary unit
- Remove network connections to the secondary unit
- Restore power to the secondary unit
- Verify that the new operating system release is loaded and that it appears to run correctly
- Power off the secondary unit again, and then reconnect its interface connections.
- Restore power to the secondary unit again
- The secondary unit should boot up and assume the standby failover role.