Re: nat.conf to NAT or not to NAT.

["Peter Strömberg" <peters_(_at_)_telia_(_dot_)_net>]

On 26 Oct 2001 at 9:50, Jan Johansson wrote:

> Hi,
> 
> I have tried to understand the nat.conf man page but I can figure
> out how to do this.
> 
> We have a number of "black" nets and three routable. I would like
> to have the black nets NATed when we go outside our gateway
> router but not inside.
> 
> Connection is like.
> 
> Internet <-> Cisco <-> Routable ips <-> Gateway <-> black nets
> 
> Gateway has 17 interfaces, 1 with routable ip and 16 different
> black nets.
> 
> So, would the rules be like
> 
> our_nets={ 128.10.10.1/24, 128.10.11.1/24, 192.168.13.1/24 }
> 
> nat on if1 ! our_nets from 192.168.1.0/24 to any ->
> 128.10.10.4/32

Internal traffic will never go out on your external interface unless 
your
routing is really screwed up.

You just need to specify your private addresses in the nat rule:

$extif="if"
$extip="128.10.10.4"
nat on $extif from 192.168.1.0/24 to any -> $extip

/Peter