We have an HQ office (Vigor 3900) and a remote LAN (Vigor 3900) linked via a point-to-point link, connected via WAN2 both ends. The P2P is externally provided and we are told is working as expected.

HQ LAN HQ WAN2 P2P Router #1 P2P Router #2 WAN2 REMOTE LAN
10.25.10.0/24 <--> 172.16.1.6 <--> 172.16.1.5/172.16.1.1 <--> 172.16.1.2/172.16.1.9 <--> 172.16.1.10 <--> 10.29.10.0/24

I am looking for a solution whereby the local LANs are automatically routed via WAN2 if they are looking to access the remote LANs

I believe this would be a static route setup on either Vigors to send remote-LAN traffic via 172.16.1.5 (for HQ) or for 172.16.1.9 (for remote LAN).

Could anyone kindly offer what they would recommend I setup ?