The Partner SD-WAN Gateway provides resiliency by detecting failures and failing over to an alternate Partner SD-WAN Gateway. This includes the ability of a Partner SD-WAN Gateway to detect failure conditions and for the surrounding infrastructure to detect failures of the SD-WAN Gateway itself.
Consider the following SD-WAN Gateway topology:
|1||Provider Edge||The Provider Edge is one instance in which failure can be detected either from the Provider Edge router pinging the SD-WAN Gateway, or from the SD-WAN Gateway to the Provider Edge router.|
|2||Call Controller||The SD-WAN Gateway should be able to ping the Provider Edge router or Call Controller to verify connectivity.|
|3||WAN||The SD-WAN Gateway should have a stateful ping responder that responds only if the WAN zone is available.|
The Partner SD-WAN Gateway also supports configurable route costs to allow for more flexible failure scenarios. Finally, there is an additional hand-off type required where neither NAT nor VLAN tags are applied to the packets and they are simply passed through to the Provider Edge router.