KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q138222: DHCP Server Delays Release of Client-Rejected IP Addresses

Article: Q138222
Product(s): Microsoft Windows NT
Version(s): winnt:3.5,3.51
Operating System(s): 
Keyword(s): 
Last Modified: 08-AUG-2001

-------------------------------------------------------------------------------
The information in this article applies to:

- Microsoft Windows NT Server versions 3.5, 3.51 
-------------------------------------------------------------------------------

SUMMARY
=======

If your computer running Windows NT Server and the Dynamic Host Configuration
Protocol (DHCP) offers and reserves an IP address for a DHCP client, and the
client takes a DHCP offer from another DHCP server, the DHCP server does not
return the offered IP address to the pool of available addresses for 15 minutes.

MORE INFORMATION
================

The following events occur when a DHCP client requests an IP address when
multiple DHCP servers are on the network:

1. When a DHCP client boots, it broadcasts a DHCPDISCOVER message to the
  network.

2. All DHCP servers in that network receive the DHCPDISCOVER message and they in
  turn send their DHCPOFFER messages via broadcast.

3. When a DHCP server sends a DHCPOFFER message, offering an IP address, the
  DHCP server reserves that IP address so that it cannot be offered to another
  DHCP client.

4. When the DHCP client accepts an IP address, the DHCP server that offered that
  address marks that address as being leased and the other DHCP servers return
  the offered IP addresses to the pool of available addresses, however, with a
  15 minute delay. The address should be returned to the available pool of
  addresses as soon as the DHCP client requests an address from another DHPC
  server.


STATUS
======

Microsoft has confirmed this to be a problem in Windows NT versions 3.5 and
3.51. This problem was corrected in the latest U.S. Service Pack for Windows NT
Workstation or Server version 3.51. For information on obtaining this update,
query on the following word in the Microsoft Knowledge Base (without the
spaces):

  S E R V P A C K


Additional query words: prodnt tcp/ip tcp brackets () sp5

======================================================================
Keywords          :  
Technology        : kbWinNTsearch kbWinNT351search kbWinNT350search kbWinNTSsearch kbWinNTS351 kbWinNTS350 kbWinNTS351search kbWinNTS350search
Version           : winnt:3.5,3.51

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.