RRAS + Using Windows 2003 server as a router

Hi Folks,

I setup windows 2003 as a router using RRAS to route 2 class C subnets together.  I have a problem that I can access computers on my existing network from my new network computers, but can not access my new network from existing network. (ping, file sharing, remote desktop…. Etc)  On Win03 which hosts RRAS, it can access both existing and new networks.  I try to match gateway from both, but it still does not work.   Please advise.  


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Renato Montenegro RusticiIT SpecialistCommented:
Please, enable IP Routing on the Registry of the Windows router:

Open: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\MSTCP
Locate: "EnableRouting"
Change to: "1"

Restart your server.

Make sure that you have pointed the default gateway on both sides to the router machine (to the respective interface). Do not setup default gateway on the router server.
pdejkongAuthor Commented:
Thanks for your advise.  I could not find the key "EnableRouting", so I made one "DWORD" + change value to "1", but it seems like it is still not work.  Any idea?  
Renato Montenegro RusticiIT SpecialistCommented:
Wrong path.... Sorry. This is the right one:

Open: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
Locate: IPEnableRouter
Change it to: 1
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Renato Montenegro RusticiIT SpecialistCommented:
Dont forget to restart before testing.
pdejkongAuthor Commented:
Umm! Computers on existing network can ping a both interface on W03 router, but still can not ping across to other computers on new network.  That is kind of weird. It sounds like traffic just stop at new network interface & don’t know how to get to the rest of new network.  (We can ping both side from W03 router.)  

On W03 router, I configure RIP of both interfaces.

Thanks again,
Renato Montenegro RusticiIT SpecialistCommented:
This registry key was just for that: allow packets to cross the server. Now, let see this:

machine_a  <-----network------> network_interface_a(router)network_interface_b <-----network----> machine_b

To allow machine_a to talk with machine_b: set machine_a default gateway to network_interface_a
To allow machine_b to talk with machine_a: set machine_a default gateway to network_interface_b

Both must be done in order to stablish any connection. When you ping, there must be a route to go and other route to go back. Thats why you need to setup both default gateways prior to test the connection.
Renato Montenegro RusticiIT SpecialistCommented:
Also, type this command at the router and post the results here:

route print

Put the ip addresses too.

If there is some missing route, ill tell you.

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