redundant VPN connection (concentrator?)

AdminSys

We have a customer with a Zyxel Flex500 and two WAN connections in our part. There is another site with one internet connection. We would like to set up the VPN connection to work redundantly on our part, if the primary WAN connection is lost, it will automatically work on the second one. Is there a description for this? Unfortunately I couldn't find it.

PeterUK

So on the site with two WAN you want to setup the VPN gateway with setting My Address Domain Name / IPv4 to 0.0.0.0 then on the remote site setup for Peer Gateway Address with primary and secondary with fall back.