> How to change the default gateway.
> I have two local area network served by m0n0wall firewall.
> Between of these m0n0wall I have a good ipsec tunnel configured.
> Site 1 : 192.168.10.1/255.255.255.0
> Site 2 : 192.168.15.1/255.255.255.0
> So I want all the traffic of the site 1 pass thru the gateway of the Site 2.
This should be done automatically. You must just set your firewall
rules correctly and then when the tunnel is up, you should be able to
ping the other network.