Setup TCP/IP Routing

Source
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defining a Gateway or manually manipulating the TCP/IP routing tables using the command-line utility ROUTE.
ROUTE.EXE is part of Windows95 and Windows NT4 and is documented in the Resource Kit:


You can get the same information by using a Command-Prompt window and
typing : "route /?" ( text-file of the output from an NT4 system )

In our example, we would enter on system#2:
ROUTE ADD 192.168.3.0 192.168.2.11
this informs System#2, that all communications for TCP/IP addresses 192.168.3.x(the '0' in the route-command translates to 'each system with an address 192.168.3.x', which in our example includes System#4) has to go via 192.168.2.11 ( which is System#3).

The rest of the Network is configured similar to Systems#1 and #2.

If you like more info on the ROUTE-command, please look at the following article in the Microsoft Knowledge Base:
http://support.microsoft.com/support/kb/articles/q158/4/74.asp

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Test your setup using PING:
Example: from System#1 :

- command : "ping 192.168.1.2" getting a reply
- command : "ping 192.168.2.11" getting a reply
System#1 can communicate with System#2 and #3 in this test.

Example: from System#3

- command : "ping 192.168.2.10" getting a reply
- command : "ping 192.168.1.1" : message "Destination host unreachable"
System#3 can communicate with System #2, but NOT with System#1.
In such cases, check on ALL system the IP-addresses, Gateway-addresses and that IP-forwarding is enabled.

And don't forget: IT MUST WORK IN BOTH DIRECTIONS, otherwise the system receiving the PING-test-signal does NOT know on which route to send the echo back !

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Browsing a system, which is accessed via a Router
Workgroups have limitations, and one of them is:
Systems on different network cables cannot be in the same workgroup !
To access a system via a router, you need to use the "Find"-command in the Windows
Start-bar and search for a "Computer" :


To avoid to get an Error-message : "The network name cannot be found" :

you need to create/update the file "LMHOSTS":
On Windows95/98, a sample-version called LMHOSTS.SAM is installed with TCP/IP in your Windows-directory. Rename/copy it to LMHOSTS and enter the IP-address with the computername. On Windows NT4/2000/XP, the files LMHOSTS and/or LMHOSTS.SAM
are located in "C:\\system32\drivers\etc".
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