RPC/TCP Connection Attempt Made Only to First Address

• Microsoft Windows NT Workstation version 4.0
• Microsoft Windows NT Server version 4.0

SYMPTOMS

In Windows NT 4.0 and prior versions, when an RPC connection is attempted using protocol binding sequence ncacn_ip_tcp, if the DNS returns a list of IP addresses for the target computer, the connection attempt will only be made to the first IP address in the list. If that connection attempt fails, the RPC connect will fail.

CAUSE

RPC only attempts to connect to the first IP address in the list returned by the Windows Sockets gethostbyname() call.

RESOLUTION

To resolve this problem, obtain the following fix or wait for the next Windows NT service pack.

This fix should have the following time stamp:

   02/24/98  5:41p                45,840 Rpcltccm.dll (Intel)
   02/12/98 12:00p                16,144 Rpcproxy.dll (Intel)

   02/24/98  5:38p                95,504 Rpcltccm.dll (Alpha)
   02/12/98 11:56a                27,408 Rpcproxy.dll (Alpha)

NOTE: This hotfix supersedes the fixes referred to in the "Windows NT 4.0 RPC Binds Hang When the Server Is Restarted" section of the following article in the Microsoft Knowledge Base:

   ARTICLE-ID: Q147222
   TITLE     : Group of Hotfixes for Exchange 5.5 and IIS 4.0

STATUS

Microsoft has confirmed this to be a problem in Windows NT version 4.0. A supported fix is now available, but has not been fully regression tested and should be applied only to systems experiencing this specific problem. Unless you are severely impacted by this specific problem, Microsoft recommends that you wait for the next Service Pack that contains this fix. Contact Microsoft Technical Support for more information.