On Thu, 2005-05-19 at 21:44 +0800, Mark Quitoriano wrote:
> here's how i did mine
> iptables -t nat -A PREROUTING -d xxx.xxx.xxx.xxx -p tcp -j DNAT
> --to-destination 10.0.0.1
>
> iptables -t nat -A POSTROUTING -d 10.0.0.1 -j SNAT --to xxx.xxx.xxx.xxx
>
> because the firewall has different ip than my mail server
>
You are forwarding it twice
Is 10.0.0.1 the internal interface of the firewall (that contains -d
xxx.xxx.xxx.xxx) or is it a seperate machine
If it is on the same machine, try this (assuming you have a FORWARD rule
too):
iptables -A FORWARD -i $EXTIF -p tcp --dport 25 -m state \
--state NEW,ESTABLISHED,RELATED -j ACCEPT
iptables -A PREROUTING -t nat -p tcp -d $EXTIP --dport 25 \
-j DNAT --to xxx.xxx.xxx.xxx
($EXTIF is the external insterface {eth0, eth1, etc.}, $EXTIP is the
external IP address)
> On 5/19/05, Peter Farrow <peter at farrows.org> wrote:
> > If you're doing true port forwarding, the internal server should see the
> > ip address of the external machine in its logs.
> >
> > This is how my machines log that do this, I use this type of entry in
> > iptables:
> >
> > iptables -t nat -A PREROUTING -p tcp --dport 80 -i eth1 -j DNAT --to
> > 10.198.0.17
> >
> > P.
> >
> >
> > Johnny Hughes wrote:
> >
> > >On Thu, 2005-05-19 at 21:08 +0800, Mark Quitoriano wrote:
> > >
> > >
> > >>i'm having a problem viewing logs on forwarded ports from the firewall
> > >>to another server, i forwarded mail(port 25) from the firewall to an
> > >>internal server. The problem is when i try to view the logs it just
> > >>shows the firewall ip as the sender and not the original sender.
> > >>
> > >>
> > >>
> > >>
> > >In reality, the firewall may be making the connection to the internal
> > >server... and not the external machine. Especially if the internal
> > >server is on a 192.168.x.x or 10.x.x.x network and you are connecting
> > >via NAT. If that is the case, the external machine is connecting to the
> > >firewall and the firewall is connecting to the internal server.
> > >
> > >
> > >------------------------------------------------------------------------
> > >
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>
>
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