/ raspberry pi

debug iptables

If you want to know how ip packets are moved in iptables tables or chains, you need add some rules in RAW table.

I always find the method out from http://backreference.org/2010/06/11/iptables-debugging/

But in my raspberry pi, I installed raspbian system, the modprobe ipt_LOG doesn't work for me, the nf_log_ipv4 module must be load, you can find it on this answer: http://serverfault.com/a/739411/140035