iptables forwarding help pls

Shwick · Sep 25, 2008, 12:39 AM

I successfully set up my home network with ip forwarding and masquerading, internet <<>> ubuntu gateway <<>> local machines.

Now i'm trying to forward a port from my ubuntu gateway to one of the machines on my lan.

Specifically I need to forward port 6112 so that I can host warcraft games. These two rules don't seem to be working.

#set DNAT
iptables -A PREROUTING -t nat -p tcp --dport 6112 -i eth0 -j DNAT --to 192.168.0.100:6112
iptables -A PREROUTING -t nat -p udp --dport 6112 -i eth0 -j DNAT --to 192.168.0.100:6112

These were some other rules I already had.

#setup MASQUERADING for nat
iptables -A POSTROUTING -t nat -j MASQUERADE

# Setup port forwarding
iptables -A FORWARD -i eth0 -o eth1 -s 192.168.0.0/24 -m state --state NEW -j ACCEPT
iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT

I set up a log after the DNAT and it gets triggered b/c I can see it in syslog, but no one can join my games.
I also set up a log after MASQUERADE but that one didn't appear in syslog.

Maybe it has something to do with state in the DNAT rules? I dunno whats going on.

Shwick · Sep 25, 2008, 08:24 PM

Stupid Windows SP3 didn't ask me if I wanted to allow War3 through my firewall. I added it manually and now my windows machine can host through the gateway. The packets were being forwarded properly all along I was just so focused on the gateway being the problem. Next time I'll install wireshark.

Sep 25, 2008, 12:39 AM	#1
Shwick DriverHeaven Newbie Join Date: Mar 2007 Posts: 16 Rep Power: 0	iptables forwarding help pls I successfully set up my home network with ip forwarding and masquerading, internet <<>> ubuntu gateway <<>> local machines. Now i'm trying to forward a port from my ubuntu gateway to one of the machines on my lan. Specifically I need to forward port 6112 so that I can host warcraft games. These two rules don't seem to be working. #set DNAT iptables -A PREROUTING -t nat -p tcp --dport 6112 -i eth0 -j DNAT --to 192.168.0.100:6112 iptables -A PREROUTING -t nat -p udp --dport 6112 -i eth0 -j DNAT --to 192.168.0.100:6112 These were some other rules I already had. #setup MASQUERADING for nat iptables -A POSTROUTING -t nat -j MASQUERADE # Setup port forwarding iptables -A FORWARD -i eth0 -o eth1 -s 192.168.0.0/24 -m state --state NEW -j ACCEPT iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT I set up a log after the DNAT and it gets triggered b/c I can see it in syslog, but no one can join my games. I also set up a log after MASQUERADE but that one didn't appear in syslog. Maybe it has something to do with state in the DNAT rules? I dunno whats going on.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Please! Turn off Automatic site forwarding!...	nbarzgar	Feedback	8	May 1, 2007 04:32 PM
please help - port forwarding for Utorrent + Limewire	benw1981	Windows XP / 2000 / NT / 9x Forum	1	May 29, 2006 12:03 PM
New Skype Adds Call Forwarding, Ringtones	Iria	Other Tech News	0	Sep 29, 2005 11:08 AM
port forwarding on a Di-604?	Nacht	Hardware Discussion & Support	10	May 19, 2004 04:36 PM
BEFSR41-CA ver.2 - Port Forwarding Is Not Working	No_Style	Hardware Discussion & Support	0	Mar 17, 2004 09:26 PM

Sep 25, 2008, 08:24 PM	#2
Shwick DriverHeaven Newbie Join Date: Mar 2007 Posts: 16 Rep Power: 0	Stupid Windows SP3 didn't ask me if I wanted to allow War3 through my firewall. I added it manually and now my windows machine can host through the gateway. The packets were being forwarded properly all along I was just so focused on the gateway being the problem. Next time I'll install wireshark.