The device attempts to restore the primary connection while the backup connection is being established. During this attempt to connect, the VPN rule set must not be recreated again – otherwise the backup connection would fail or an existing VPN connection would simply be torn down.
To prevent this, initial "Dynamic VPN" negotiations with the primary connection's remote site are performed. If these negotiations are successful, the primary connection can be reestablished. To this end, the backup connection is disconnected and the backup status is reset. This prevents the backup connection from being reestablished immediately. Only after this is the primary connection reestablished with the original VPN rules.
Important: The use of the "Dynamic VPN" connection between branch office and switching node is a necessary condition for the backup function described here.
