INF: How to Configure NWLink to Run SQL Srv with Multiple NICs

ID: Q137787

The information in this article applies to:

Microsoft SQL Server version 6.0

SUMMARY

When you run Microsoft SQL Server on a computer running Windows NT with multiple Network Interfaces Cards (NICs), you may need to configure the NWLink IPX/SPX Compatible Transport with a non-zero internal network number. This is necessary if you want to connect to the SQL Server through every NIC via IPX/SPX.

MORE INFORMATION

By default, the "internal network number" parameter is set to zero for the NWLink IPX/SPX Compatible Transport, even with multiple NICs. This means that the IPX address for this machine is the same as the first NIC MAC address, and the "internal network number" parameter does not take effect. The default setting works fine for a single NIC computer, and in fact is the recommended configuration.

With two or more NICs, problems can arise using the default settings. Since the Windows NT default IPX address is the MAC address of the first NIC, SQL Server will only listen on the first NIC, making it impossible to connect to the SQL Server through other NICs.

By configuring the NWLink with a unique non-zero "internal network number," Windows NT is given a logical IPX address with the "internal network number" as the network number and "000000000001" as the IPX address. In this case, SQL Server will listen on this logical address, and clients can connect to the SQL Server through every NIC using internal routing. For example, if you set the "internal network number" to "12345678," then SQL Server will broadcast Service Advertising Protocol (SAP) packets with "12345678.000000000001.843E" as the IPX internetwork address, where 843E is the default IPX socket used by SQL Server.

For additional information about how to verify the IPX internetwork address used by SQL Server SAPs, please see the following article in the Microsoft Knowledge Base:

Q112713 : INF: Verify Registration of SQL Servers in NetWare Binderies

To find out the current NWLink configuration, you can execute the NT command "IPXROUTE CONFIG" at the command prompt. If more than one MAC address is displayed as indicated by "NET1...", "NET2...", and so forth, and the "IPX internal network number" is zero, then you should use the Control Panel, Network, NWLink IPX/SPX Compatible option to set the "internal network number."

In certain situations, "IPXROUTE CONFIG" can return multiple entries, even though you have ensured that there is only one NIC installed. This can occur if you also have other communication software installed, such as Microsoft Remote Access Service (RAS). In this case, you should treat the configuration as a multiple NIC situation and set the "internal network number" accordingly.

Additional query words: sql6 multi-nic windows nt lan

Keywords : kbinterop kbnetwork SSrvLAN
Version : 4.21 | 6.0
Platform : WINDOWS
Issue type :