Routing and Remote Access with a Null Serial Cable

• Microsoft Windows NT Server version 4.0
• Microsoft Routing and Remote Access Service Update for Windows NT Server 4.0

SUMMARY

The information in this article explains how to setup a Dial-on-Demand (DOD) connection between two Routing and Remote Access Service (RRAS) Servers using a null serial cable.

MORE INFORMATION

The following steps assume that you have already installed Routing and Remote Access Service and that it is operating correctly. Perform the following steps on both servers:

1. Click the Start button, point to Settings, click Control Panel, and then double-click the Modems icon.

2. Click Don't detect my modem; I will select it from a list and click Next.

3. Click Dial-Up Networking Serial Cable between 2 PCs, and then click Next.

4. Click the physical com port to which the cable is attached, and then click Next.

   NOTE: If this is the first modem that you have installed you will now need to enter the area code and any dial out prefix that is required.

5. Restart your server.

6. Click the Start button, point to Settings, click Control Panel, and then double-click the Modems icon. Verify the modem properties on both servers and make sure the maximum speed matches.

   NOTE: It is best to start at 9600 bps and increase it later to a speed that does not give serial overruns. Each time you change the speed, you will need to stop and restart Routing and Remote Access Service for the change to take effect.

7. Start Routing and Remote Access Service Administrator and add a DOD interface on both servers, using the following steps:

   a. Click LAN and Demand Dial Interfaces.

   b. Click Actions, click Add Interface…, and then type the name for your

         DOD connection. For the sake of simplicity, use the same name on
         both servers.
   

   c. Click Next.

   d. Click the appropriate routing options to enable them.

         For example, if you are using Routing Information Protocol (RIP) for
         IP then you would enable the option Route IP packets on this
         interface.
   

   e. Click the following options to create the user accounts:

         1. Add a user account so a remote router can dial in
            Authenticate remote router when dialing out
   
      f. Click Next, click Dial-Up Networking Serial Cable between 2 PCs
         (ComX), and then click Next.
   
         where X is the com port number.
   
      g. Leave the phone number blank, and then click Next.
   
      h. Enter the same name that you used in step b for the User Name,
         Password, and Confirm Password.
   
      i. Click Next and type the same name as steps b and h for the Password
         and Confirm Password.
   
      j. Click Next, and then click Finish.
   
   

8. Click the desired routing protocols, and then accept the default options.

9. Once both DOD Interfaces are created, from one server only in Routing and Remote Access Service Administrator, click LAN and Demand Dial Interfaces. Right-click on the new DOD interface, and then click Connect.

1. In Routing and Remote Access Service from both servers, expand IP Routing and/or IPX Routing depending on which routing protocols you have installed.

2. Click Summary, right-click the DOD interface, and then click Update Routes.

3. Click Static Routes, and if the routes were exchanged successfully, you should see the routes from the opposite server.

Troubleshooting

If you are experiencing problems connecting or exchanging routes between the two servers, check for one or more of the following:

• Check the modem properties and verify the Maximum Speed for the Serial Cable connections match on both servers.

  -or-

• From both servers, verify the Initial Speed setting by performing the following steps:

  1. In the Routing and Remote Access Service Administrator, click LAN

        and Demand Dial Interfaces.
  

  2. Right-click the new DOD interface, and then click Configure

        Interface.
  

  3. Click Configure, and verify that Initial Speed matches the Maximum

        Speed in the modem properties, and that these speeds match the other
        server.
  

        NOTE: It is imperative that if you make any changes to the modem
        properties, Routing and Remote Access Service must be stopped and
        restarted.
  

  -or-

• If both servers seem to be connecting successfully but cannot exchange RIP routes or clients on either side of the routers cannot communicate but the servers can, then check to see if a RAS connection was made instead of DOD using the following steps:

  1. In the Routing and Remote Access Service Administrator, click LAN

        and Demand Dial Interfaces.
  

  2. Verify that the Connection State for the DOD interfaces are

        displaying Connected.
  

        NOTE: If only the dialing computer shows connected, then, most
        likely, a RAS connection has been made. If this is the case, check
        to see that the User Name being used in the credentials on the
        dialing server matches the name of a DOD interface on the server
        being dialed.