Question: A local ISP hosts our SQL Server, but I cannot see or connect to a named instance running on this computer. I know that the SQL Server 2000 naming instance does not use the TCP/IP port 1433, and is sure that the TCP/IP port used by the SQL Server instance is open. Do you have any suggestions?
Answer:: Many people know how to use the SQL Server network utility or SQL Server error log to determine the listening port of the SQL Server instance. However, many people seem to have forgotten or do not even know that UDP port 1434 must be opened to ensure that you can access and browse named instances correctly. I suggest you carefully study this requirement. Search "1434" in SQL Server online books and you will get three valuable search results. In my SQL Server practical skills column published on February 14, July 2001 on the SQL Server Magazine website, you can also find information about accessing the named instance (InstantDoc ID 21127 ). I would like to explain it briefly here. SQL Server creates a listening service on UDP port 1434, allowing the client to query a list of named instances and their network configurations from the Server. The listening service is always running on UDP port 1434 and cannot be changed.
-Brian Moran
