[Openswan Users] Single interface / tunnel will not come up.

[Mike Johnston]

I also recall having to open up the firewall on the server to get it to 
pass traffic.  Something like this on ubuntu:

sudo ufw allow from 1.1.1.1 to 2.2.2.2 port 500 proto udp
sudo ufw allow from 1.1.1.1 to 2.2.2.2 port 4500 proto udp
sudo ufw allow from 1.1.1.1 to 2.2.2.2 proto esp