IP Forwading from Local IP to Live IP

Jason Opperisano opie at 817west.com
Tue Apr 19 13:42:26 CEST 2005


On Tue, Apr 19, 2005 at 03:55:18PM +0800, elg3ne wrote:
> Hi guys, Im new to iptables.. hope someone can help me to this.
> 
> The situation is this, I have a webserver running on a local network machine
> (192.168.1.3) & I want it to be accessible outside my network. Is it
> possible?
> 
> setup is like this:
> 
> workstation (192.168.1.3) ---> HUB ---> server ( LIVE IP, accessible
> everywhere on the net )
> 
> when user access the live IP ex. 10.0.0.3 can he forward to get the files on
> the worstation?

three line guide to "port-forwarding:"

  iptables -t nat -A PREROUTING -i $EXT_IF -p tcp --dport $OUTSIDE_PORT \
    -j DNAT --to-destination $INSIDE_HOST_IP:$INSIDE_PORT

  iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT

  iptables -A FORWARD -i $EXT_IF -p tcp --syn \
    -d $INSIDE_HOST_IP --dport $INSIDE_PORT -j ACCEPT

where example values for all the variables are:

  EXT_IF="eth0"
  OUTSIDE_PORT="80"
  INSIDE_HOST_IP="192.168.1.3"
  INSIDE_PORT="8080"

HTH...

-j

--
"Peter: Lois, When I'm through with them, our kids will be so smart,
 they'll be able to program their own VCRs without spilling piping hot
 gravy all over myself."
        --Family Guy



More information about the netfilter mailing list