Windows 2003 routing with three network cards

[VictorD]

I am setting-up a test environment of a distributed system.

The network has three distinct subnets: "Front" (172.16.100.0),
"Back"(10.237.0.0) and "Internet" (192.168.1.0). I have configured
Windows 2003 Server Routing services on a dedicated server to act as a
router (server name is "Router"). I setup static routes between the
Front and Back networks so now the Front and Back networks can
communicate as needed. Now I would like to have both the Front and
Back networks access the internet via the third network interface
called "Internet".

I have been unsuccessful so far. The communications are fine between
the Front and Back, but neither can get to the internet. The Router
can reach the internet after adding a default route on the router.


I have clients in the Front network with a gateway defined as the
Router's IP that is on the same network as the client
(172.16.100.254).

The router has it's gateway defined as the NIC's IP which goes to the
Internet (192.168.1.158).

So my logic was to have the gateway of the client direct traffic to
the router's interface that it could see, and then magically as it
hits the router, it will find that this is needing to go to the
router's default gateway
which is the router's internat NIC. Sounded great but it obviously
does not work that way as I cannot get the thing to direct any traffic
out the internet NIC.

~Vic

 

[Phillip Windell]

I am setting-up a test environment of a distributed system.

The network has three distinct subnets: "Front" (172.16.100.0),
"Back"(10.237.0.0) and "Internet" (192.168.1.0). I have configured
Windows 2003 Server Routing services on a dedicated server to act as a
router (server name is "Router"). I setup static routes between the
Front and Back networks so now the Front and Back networks can
communicate as needed.

There should be *no* static routes on this router. You subject line
indicates the box has three nics, therefore it already "lives" on all three
networks at the same time. Therefore these are classifed as "Directly
Connected Networks" and these never require static routes because the router
already knows where they are.

Use the command line "Route -f" to clear the table of bad routes and then
reboot to rebuild the table properly.

All clients use the same router as thier Default Gateway, *but* they must
use the IP# of the router interface that directly faces them.

If your "internet" subnet of 192.168.1.0 is "fictional" then there is
nothing else to do, but if it is real, then there must be some kind of
firewall device between this router and the Internet since the 192.168.1.x
address set is not compatible with the Internet. The "firewall device" would
require static routes for the 172.* and 10.* networks. It would not need one
for 192.168.* because that would be a "directly connected network" to the
firewall device.