Close, here is some ascii art to try and describe it.

|----------------|                                  |-------|(corp lan)
|Privet net      |                                  |gateway|(world)
|192.168.123.0/24| <----------> eth0 192.168.123.100|-------|eth1
|----------------|              eth0:0 192.168.0.100         172.16.0.3
                                 eth0:1 10.0.0.100

What I am looking for is when I bring a box in at 192.168.0.101 that the 
router will not send that traffic through to the world but will NAT or 
route it through the appropriate device.
For example if 192.168.123.2 want to go to google the gateway will nat 
it but if it wants to talk to a raid at 192.168.0.101 it will route or 
nat that through the gateway.
Jason
P.S. I im in way over my head so be gentel :)

Anton Yurchenko wrote:
> Jason Sievert wrote:
> 
>> Ok all ye networking gurus, I am looking for some information on 
>> setting up a gateway/router for my lab at work.  I have the basic 
>> setup, two network card, one private for the lab and one public for 
>> net access and to allow certain computers to get back in.  the privet 
>> network is NATed when they go for outside access.  The internal ip 
>> address is at 192.168.123.0/24.  Now my question is that when we bring 
>> in equipment in from vendors it is normally set up with a default ip 
>> address, like 10.0.0.12 or 192.168.0.101. What I would like to do with 
>> virtually ip address, routing, or iptables is set up a why that the 
>> 192.168.1230/24 net can access the other networks on the same physical 
>> segment via this gateway?
>>
> so the way that I understand is that you have some host in internal net, 
> going via the linux gateway. but when you bring in some new hardware 
> with different IPs you`d like for all you internal hosts to use it as a 
> gateway? I hope I got it correctly.
> You can of course change the default gateway on all your hosts, or you 
> can add the secondary IP in the subnet of the new hardware, on you 
> router internal interface, and point the default gateway to it instead 
> of outside. the packets will go to the linux router and from it to new 
> hardware and then to outside.
> I hope i got you network topology correctly
> 
>> Thanks gang,
>> Jason
>>
>> _______________________________________________
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>> http://www.mn-linux.org tclug-list at mn-linux.org
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>>
> 
> 
> _______________________________________________
> TCLUG Mailing List - Minneapolis/St. Paul, Minnesota
> http://www.mn-linux.org tclug-list at mn-linux.org
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