I successfully deployed a racoon on my Debian 7.0 droplet earlier today and at that time it works fine. I noticed a “routing loop” problem after I restarted racoon, and I ran :
“`iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

After that the "routing loop" problem disappeared, but racoon showed another error: 
ERROR: unknown Informational exchange received.
What should I do then? (IPv4 forwarding has been enabled.)Thank you.