[CentOS] Port Forwarding woes

Mon Apr 27 16:01:06 UTC 2009
Dan Carl <danc at bluestarshows.com>

Bo Lynch wrote:
> I'm having some port forwarding issues issues with iptables.
> We are using iptables as a firewall with 2 nics and on ip alias.
> I'm trying to port forward on the alias ip
> eth0 = 65.x.x.1
> eth0:1 = 65.x.x.2
> eth1 = 192.168.x.x
>
> I'm wanting to forward certain ports(80,5071...etc) that makes request on
> eth0:1 IP 65.x.x.2 to forward to internal IP 192.168.x.x. I have setup the
> following rules but I must be doing something wrong.
> iptables -t nat -A PREROUTING -p tcp -i eth0 -d 65.x.x.2 --dport 80 -j
> DNAT --to-destination 192.168.x.x:80
> iptables -t nat -A PREROUTING -p tcp -i eth0 -d 65.x.x.2 --dport 5071 -j
> DNAT --to-destination 192.168.x.x:5071
> iptables -A FORWARD -p tcp -i eth0 -d 192.168.x.x --dport 80 -j ACCEPT
> iptables -A FORWARD -p tcp -i eth0 -d 192.168.x.x --dport 5071 -j ACCEPT
>
> Any help would be greatly appreciated.
> Thanks
>   
Try

iptables -A FORWARD -p tcp -i eth0 -o eth1 -d 192.168.x.x --dport 80 -j ACCEPT
iptables -A FORWARD -p tcp -i eth0 -o eth1 -d 192.168.x.x --dport 5071 -j ACCEPT