FTP Server Fails to Respond If First Binding Does Not Work

• Microsoft Windows NT Server version 4.0
• Microsoft Windows NT Server, Enterprise Edition version 4.0
• Microsoft Internet Information Server versions 3.0, 4.0
• Microsoft Windows NT Server version 4.0, Terminal Server Edition

SYMPTOMS

Multihomed FTP server fails to respond to simple commands like DIR or GET.

CAUSE

If an Internet Information Server FTP server is running on a computer with two network interface cards and the first interface is not available (connection broken, for example). You will only get the normal status line from the FTP server.

RESOLUTION

Outgoing FTP traffic goes out the first entry in the route table to that network. On a multihomed computer on the same IP network, all outbound traffic will exit on the card that has the first entry in the route table. If you change the IP address of that card, it will change the location in the route table.

To resolve this problem, obtain the latest service pack for Windows NT 4.0 or Windows NT Server 4.0, Terminal Server Edition. For additional information, please see the following article in the Microsoft Knowledge Base:

Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack

STATUS

Microsoft has confirmed this to be a problem in Windows NT 4.0 and Windows NT Server 4.0, Terminal Server Edition. This problem was first corrected in Windows NT 4.0 Service Pack 4.0 and Windows NT Server 4.0, Terminal Server Edition Service Pack 4.

MORE INFORMATION

With this fix, FTP makes back connections using the source IP address that the client connected to. This fixes problems with firewalls and any device that is expecting this behavior.

Keywords : NT4SP4Fix kbbug4.00 kbfix4.00.sp4
Version : WinNT:3.0,4.0
Platform : winnt
Issue type : kbbug