Re: iptables - lo interface problem

> On Mon, 23 Aug 2004 18:09:16 -0400, Travis Fraser <travis@xxxxxxxxxxxxx>
wrote:
> > On Mon, 2004-08-23 at 17:29, Mike Burger wrote:
> > > On Mon, 23 Aug 2004, Rodolfo Alcázar wrote:
> > >
> > > > From: "Mike Burger" <mburger@xxxxxxxxxxxxxxxxx>
> > > >
> > > > > On Mon, 23 Aug 2004, Rodolfo Alcázar wrote:
> > > > >
> > > > > > > Errr, this is a classic case for a split DNS setup, you need
to setup
> > > > > > > DNS to point to it's DMZ interface on/within the firewall, or
just add
> > > > > > > it in the hosts file, don't try to connect to the external
interface
> > > > > > > and use the NAT, it don't work that way. I could be wrong.
> > > > > > >
> > > > > > > Yang
> > > > > >
> > > > > > Thanks, Yang. I didn´t heard about split DNS setup. I will try
it. Best
> > > > > > regards.
> > > > >
> > > > > In the meantime, you can use something like this (I used this
until split
> > > > > DNS came into play on my network):
> > > > >
> > > > > $IPTABLES -t nat -A PREROUTING -i internal-interface -d
> > > > your.external.ip.address -j DNAT --to your.internal.destination.IP
> > > > > $IPTABLES -t nat -A POSTROUTING -o internal-interface -d  -s
> > > > your.internal.netowrk/netmask -j SNAT  --to
firewall's.internal.ip.address
> > > > > --
> > > > > Mike Burger
> > > > > http://www.bubbanfriends.org
> > > >
> > > > Thx, mike. This is the solution I was expecting for, but I think the
split
> > > > DNS is my right answer. I will do the same as you, use this rules in
the
> > > > meantime. Best regards.
> > >
> > > Happy to help.
> > >
> > > If you need an example of a split DNS config, let me know.  I'm using
it,
> > > now, in lieu of the routing routing option.
> > > --
> > > Mike Burger
> >
> > Hi Mike,
> >
> > I would like to see the split-DNS config. This thread is very timely for
> > me as I am setting up the exact arrangement in my network.
> >
> > Thanks,
> > Travis Fraser
> >
> hi,
>
> A simple split dns configuration really is just using your internal
> DNS as the primary and some external public DNS as the secondary in
> the DNS name resolving order.
> #/etc/resolv.conf
> domain mydomain.com
> nameserver xxx.xxx.xxx.xxx (my internal dns with private LAN info only)
> nameserver xxx.xxx.xxx.xxx (some external public DNS for public name
resolution)
>
> the catch is you setup the internal DNS zone recrods using the
> internal IP of servers so you do not resolve them with external IPs
> they might be NATed with on the public DNS server. DO NOT allow any
> external hosts to query the same DNS server for your domain!
>
> and for anything else, you can either setup the same server for
> forwarding or failover to the configured secondary public server to do
> the name resolution.
>
>
> Yang
>

Travis, based on Yang´s idea, I checked the BIND9 docs, and find a very
simple named.conf parameter: "view". If you use BIND9, you can try this,
also,
it is very easy & simple (you do not need to start another daemon), here is
a
simplification of my named.conf file (the only differences between internal
and
external zones is myzone /myzone.LOCAL file, where you store your
differentiated records, and the matched clients):

options {
            directory "/var/named";
            // some lines deleted for security reasons
            };

view "internal" {
            match-clients { 127.0.0.1; 192.168.0.0/16; };
            zone "myzone.org" IN {
                        type master;
                        file "myzone";
            };
            // some lines deleted for security reasons
};

view "external" {
            match-clients { any; };
            zone "myzone.org" IN {
                        type master;
                        file "myzone.LOCAL";
            };
            // some lines deleted for security reasons
};

I suppose I have security issues I must solve, but this is the idea. If
anyone find which security issues we must address, please write the list

Best regards,

Rodolfo