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Q175952: NETSTAT Displays a LISTENING Port with IP Address 0.0.0.0

Article: Q175952
Product(s): Microsoft Windows NT
Version(s): WinNT:4.0
Operating System(s): 
Keyword(s): kbnetwork
Last Modified: 09-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Workstation version 4.0 
- Microsoft Windows NT Server version 4.0 
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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.
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Keywords          : kbnetwork 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400
Version           : WinNT:4.0

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