Can't get port forwarding to work on Ubuntu

Posted by Znarkus on Server Fault See other posts from Server Fault or by Znarkus
Published on 2012-09-22T12:43:30Z Indexed on 2012/09/22 15:39 UTC
Read the original article Hit count: 143

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ubuntu

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iptables

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port-forwarding

I'm using my home server as NAT/router, which works well. But now I'm trying to forward port 3478, which I can't get to work.

eth0 = public interface
eth1 = private network

$ cat /proc/sys/net/ipv4/conf/eth0/forwarding
1
$ cat /proc/sys/net/ipv4/conf/eth1/forwarding
1

Then to forward port 3478 to 10.0.0.7, I read somewhere that I should run

iptables -t nat -A PREROUTING -p tcp -i eth0 --dport 3478 -j DNAT --to-destination 10.0.0.7:3478
iptables -A FORWARD -p tcp -d 10.0.0.7 --dport 3478 -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT

I also ran

ufw allow 3478

But testing port 3478 with http://www.canyouseeme.org/ doesn't work. Any idea what I have done wrong?

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