NETSTAT Displays a LISTENING Port with IP Address 0.0.0.0

ID: Q175952

The information in this article applies to:

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

SYMPTOMS

When you carry out the command netstat -an, you may receive a display that shows an IP address of 0.0.0.0 in LISTENING status similar to the following:


   TCP   0.0.0.0:110   0.0.0.0:0   LISTENING

NOTE: The normal, or expected, behavior is to have your local computer's IP address listed instead of 0.0.0.0.

CAUSE

The Winsock application that is listening on the designated port was written so that it binds to any local IP address by using INADDR_ANY. This means that the application will listen to all local interfaces and you can connect to the port of any of them. This is why netstat -an shows IP address 0.0.0.0 listening on the port.

MORE INFORMATION

This is by design. However, if you do not want the Winsock application to listen to all local interfaces, it must be designed to bind to a specific IP address. Netstat.exe will then show a local IP address in LISTENING status.

NOTE: Netstat.exe began displaying TCP ports that are in LISTENING state with Windows NT 4.0 Service Pack 3.

Keywords : kbnetwork ntnetserv ntprotocol nttcp NTSrvWkst ntutil
Version : WinNT:4.0
Platform : winnt
Issue type :