INF: How to Debug SQL Server Connectivity Problems Over RAS

• Microsoft SQL Server, versions 4.21 and 6.0

SUMMARY

You can use Microsoft Remote Access Service (RAS) to connect to Microsoft SQL Server from Windows NT, Windows 95, or Windows for Workgroups clients. Because SQL Server communicates with its clients using high-level InterProcess Communication (IPC) APIs only, such as named pipes, TCP/IP sockets, and IPX/SPX sockets, the support for RAS is transparent, which means that SQL Server does not care whether this is a RAS connection as long as the RAS service supports the appropriate IPCs used by the SQL Server clients. SQL Server can run either on the same computer where the RAS server service is running or on a different computer that is connected to the RAS server through a LAN. The key to troubleshooting connectivity problems through RAS is to isolate the problems to either Windows NT/network/RAS issues or SQL Server connectivity issues.

MORE INFORMATION

Windows NT RAS supports TCP/IP, IPX/SPX, and NetBEUI LAN protocols. When you install the RAS service, you can choose to enable one or all of these protocols, which in turn provides support for IPCs including named pipes, TCP/IP sockets, and IPX/SPX. Although it is recommended that NetBEUI be enabled for named pipes communication, you can use any one of those protocols for named pipes connections to SQL Server, as long as the SQL Server computer has the same protocol installed. Depending on the clients you use, you may or may not have all of the IPCs available. If the clients are Windows NT or Windows 95, all of the IPCs above are available. For Windows 3.1 or Windows for Workgroups 3.11 clients, only the named pipes IPC is available.

Depending on the IPCs used, the troubleshooting techniques are different:

1. Named pipes: If you are using named pipes as the IPC, you can run the easy makepipe/readpipe test. This pair of utilities comes with all versions of SQL Server. Please consult the SQL Server documentation if you need any help using these utilities.

   If the pipe test fails, it indicates this is a Windows NT/Network/RAS problem. You should note the return status of the READPIPE, and contact your primary Windows NT/Network support provider if you do not know how to diagnose the problem based on the return status.

2. TCP/IP sockets: If you are using TCP/IP sockets through RAS, the first test you should run is the PING utility. If the PING fails from either the client or server side, it indicates a problem with Windows NT/Network/RAS, and again you should contact your primary Windows NT/Network support provider for help.

   If the PING test succeeds, this may not be a RAS specific issue. To verify, you can try connecting from a regular LAN client or from the local server through TCP/IP sockets. For more information about troubleshooting SQL Server connections via TCP/IP, see Knowledge Base article Q107647 ("INF: Connecting to SQL Server from TCP/IP Sockets Clients).

3. IPX/SPX sockets: If your RAS client can not connect to SQL Server via IPX/SPX, check the following:

       - Verify this is a RAS-specific issue by plugging this RAS client
         into the LAN and use the Network Interface Card (NIC) to connect. If
         it still fails, it is not a RAS-specific issue. See Knowledge Base
         article Q107494 ("INF: Connecting to SQL Server from NetWare
         Clients") for information about how to troubleshoot IPX/SPX clients
         in general.
   

       - Verify that RAS is working properly by attaching this RAS client to
         a NetWare file server on the network. If it fails, it means the RAS
         client or server is not installed correctly, and you should contact
         your primary Windows NT/Network/RAS support provider for further
         help.
   

       - Use "ISQL /L" or "List Servers" in other SQL Server utilities to
         verify that this RAS client can see the SQL Server as listed. If SQL
         Server is not shown in the list, it means this client is attached to
         a NetWare file server which does not contain the SQL Server service
         object in its bindery. If this is a Win32 SQL client, please see
         Knowledge Base article Q130744 ("PRB: Connection Problems from
         Clients via IPX/SPX").
   

       - If "ISQL /L" or "List Servers" does not display the SQL Server, you
         can also use a direct connection to SQL Server through hardcoding the
         IPX address of the server computer. See Knowledge Base article
         Q138716 ("INF: How to Debug Direct Connections to SQL Over IPX/SPX")
         for more information.
   

       - If SQL Server and RAS server are running on the same computer, you
         need to make sure that you set the "internal network number" with a
         non-zero number that is unique among all network segment numbers for
         the NWLink IPX/SPX Compatible transport. This is needed because the
         computer would behave like one with multiple NICs when the RAS server
         is running on the same computer. See Knowledge Base article Q137787
         ("INF: How to Configure NWLink to Run SQL Srv with Multiple NICs")
         for more information.