DOCUMENT:Q148939 09-AUG-2001 [winnt] TITLE :DHCP Server Creates Unnecessary Lease PRODUCT :Microsoft Windows NT PROD/VER:winnt:3.5,3.51 OPER/SYS: KEYWORDS:kbnetwork ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Workstation versions 3.5, 3.51 - Microsoft Windows NT Server versions 3.5, 3.51 ------------------------------------------------------------------------------- SYMPTOMS ======== When a Dynamic Host Configuration Protocol (DHCP) server makes an address offer to a client and the client chooses an address from a different DHCP server, the server that was not chosen keeps a DHCP lease for the offered address for 15 minutes. CAUSE ===== When multiple DHCP servers put out address offers to a client, the server whose offer is not accepted goes through a cleanup procedure. This procedure should remove the address which was temporarily set aside from the previous offer. However, this is not the case. The cleanup procedure is not clearing the temporarily assigned lease out of the database. RESOLUTION ========== To resolve this problem, install the fix mentioned below. The temporary lease will last for 15 minutes. If you have extra leases you can just let the lease expire. Some companies are very short on available leases and cannot afford this, so a correction to DHCP has been created. STATUS ====== Microsoft has confirmed this to be a problem in Windows NT version 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 ====================================================================== Keywords : kbnetwork Technology : kbWinNTsearch kbWinNTWsearch kbWinNT351search kbWinNT350search kbWinNTW350 kbWinNTW350search kbWinNTW351search kbWinNTW351 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. Copyright Microsoft Corporation 2001.