Re: Local rule for Port Forward

[Patrick Nelson <pnelson@neatech.com>]

On Fri, 2003-04-25 at 14:12, David Gaudine wrote:
> > I'm doing port forwarding to a server that runs jabber and everything
> > works fine, I did notice that if I bring up a jabber client on the
> > firewall itself I do not get connected.  While this isn't really
> > needed... I don't totally understand why it doesn't work.  Being
> > inquisitive... well I just gots to know why!  Can anyone shed some
> > light?
> > 
> > My rules for the jabber port forward are:
> > 
> > iptables -A FORWARD 
> >          -i $ExIF -d $JabIP -p tcp --dport $JabPort 
> >          -j ACCEPT
> > iptables -A PREROUTING 
> >          -t nat -d $ExIP -p tcp --dport $JabPort
> >          -j DNAT --to-destination $JabIP
> > iptables -A POSTROUTING
> >          -t nat -d $JabIP -p tcp --dport $JabPort
> >          -j SNAT --to-source $InIP
> 
> I'm new at this, but shouldn't you have INPUT and OUTPUT rules
> if you want to run something on the firewall?  Maybe not, since
> I've just mastered FORWARD, INPUT and OUTPUT and I haven't
> figured out where PREROUTING and POSTROUTING come in
> so maybe you're counting on them to do the job.
> 

Yes, and these are not the only rules to the script.  But these are the
only ones that pertain to Jabber.  Might be an INPUT OUTPUT issue... I
just don't see why seeing the local network has accept rights to the
firewall.