Dear Juan, see the section on logging in the wiki: https://wiki.archlinux.org/index.php/Iptables#Logging Cheers Bastian On Sun, Aug 26, 2012 at 7:11 PM, Juan Diego Tascón <juantascon@xxxxxxxxx> wrote: > Thanks for both replies. The graphic does it a lot more > understandable. Is there any way to debug iptables, I mean, like a > tool where I can visualize the path of a packet and where exactly it > gets dropped/accepted and also realtime packets headers (src, dst, > proto, dport, sport, etc)? > > On Sat, Aug 25, 2012 at 12:56 PM, Corrado Primier <ilbardo@xxxxxxxxx> wrote: >> 2012/8/25 Juan Diego Tascón <juantascon@xxxxxxxxx>: >>> Good day, >> >> Hello :) >> >>> I'm thinking of >>> setting the default FORWARD policy to ACCEPT as my default INPUT >>> policy is DROP and unless there is a valid FORWARD rule for a given >>> port the packets wont go anywhere. I'm I right on this? >> >> You're wrong. Either a packet goes through the INPUT chain or it goes >> through the FORWARD chain, depending on its destination. Take a look >> at this packet flow diagram: >> http://www.linuxhomenetworking.com/wiki/images/f/f0/Iptables.gif >> >> Corrado -- Bastian Beischer RWTH Aachen University of Technology @CERN Office: Bdg 32-4-B12 Phone: +41-22-76-75750 E-mail: bastian.beischer@xxxxxxx Address: CERN, CH-1211 Geneve 23 @RWTH Aachen Office: 28 C 203 Phone: +49-241-80-27205 E-mail: beischer@xxxxxxxxxxxxxxxxxxxxx Address: I. Physikalisches Institut B, Sommerfeldstr. 14, D-52074 Aachen