[Openswan Users] Configure net-to-net vpn with both vpn, servers behind adsl nat routers

[Utkarsh Shah]

> Hi, I have the following scenario, and I would like to create a vpn with
> natt suport.
>
> LAN_1 ------ vpn server --- router adsl ------ internet---- router adsl
> ----- vpn server ----- LAN_2
>
> I've installed:
> openswan-2.4.7.tar.gz<http://www.openswan.org/download/openswan-2.4.7.tar.gz>
>
> I'm working with slackware 10.1 and kernel 2.16.12
>
> I have to install the kernell natt patch??
>
> Could someone help me with ipsec.conf file? I've been searching the internet
> without any result...
>
> Thanks.
>
> Xavi
i have achieved above scenario with following changes it might not be 
perfect solution...
on adsl router apply portforwarding rules for UDP port 500 port 4500 and 
proto esp(50) to your vpn server on both end

configure your ipsec.conf as below

conn net-to-net
	left=10.0.1.2
	leftid=@leftid
	leftsubnet=192.168.0.0/24
	right=remoteserver(domain name or ip which will identify adsl router)
	rightid=@rightid
	rightsubnet=192.168.1.0/24
	authby=secret
	auto=start

and your ipsec.secret as

@leftid @rightid : PSK "your preshared key"



Regards,
Utkarsh Shah