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Ipsec - routing private multihomed subnets

While setting up ipsec - and findout that you can reach one network but not the other by seeing the working network (on both routes) routes via the ipsec tunnel from private <==> private net.

On the other network you see the router (usually multihomed) trying to route traffic to that network from the public interface <==> private net.

One has to tell the router to SNAT to the private net:

Assuming:

Destination network: 10.8.139.14/31

Source network: 192.168.0.0/23

Routing via private network router/gw: 192.168.0.250

$IPT -t nat -A POSTROUTING -d 10.8.139.14/31 -s 192.168.0.0/23 -j SNAT --to-source 192.168.0.250