I have a dual wan configuration WAN1 and WAN2 with a classic dual wan mangle configuration (marking connection and in postrouting/outupu marking routing)
The router is an IPSEC client
IPSEC can only work if the connection is established through WAN2.
I have to enforce that the connection established from the router for the IPSEC VPN has to be routed to WAN2.

IPSec connection is established from the client that is in the router itself.
In which chain do I have to mark the connection to enforce that all connections to the VPN Server (fixed IP p.p.p.p) are routed to the WAN2?