Example of Stateful Synchronization

In case of a failover, the following sequence of events occurs:

1. A PC user connects to the network, and the Active Security Appliance creates a session for the user.
2. The Active Security Appliance synchronizes with the Standby Security Appliance. The Standby now has all of the user’s session information.
3. The administrator restarts the Active unit.
4. The Standby unit detects the restart of the Active unit and switches from Standby to Active.
5. Now Active Security Appliance begins to send gratuitous ARP messages to the connected switches using the same Virtual MAC address and IP address as the Active Security Appliance. No routing updates are necessary for downstream or upstream network devices.
6. When the PC user attempts to access a Web page, now Active Security Appliance has all of the user’s session information and is able to continue the user’s session without interruption.