Hi, We have a cluster node with multiple SQL Server 2005 instances. Since these instances have different IP addresses can we use the same default TCP/IP port 1433 for all of these instances or should we use different non standard port numbers for these instances? Could any one please help me with this issue? Thank you, Yours, SQLBuddy
You can't use the same defaultTCP/IP port 1433 for all of these instances on the same server. for same port# , you get error: TDSSNIClient initialization failed with error 0x2740, status code 0xa. Reason: Unable to initialize the TCP/IP listener. Only one usage of each socket address (protocol/network address/port) is normally permitted. you can: Use different Static port numbers for these instances, and connection string for server is IP,port# example; 192.168.1.39,5000 Use dynamic port (sql browser should be runnung), i don't recommend using dynamic port. You can create alias on client machines for the server,port#.
This is not quite correct regarding the port numbers. You can only have one default instance in a cluster and this is due to the name of the SQL Service - MSSQLSERVER. The named instances in the cluster can have the same port (1433, even) if desired, because the ports are allocated per IP address, not by machine. This is because each instance is its own cluster resource with its own IP address.