Microsoft KB Archive/276324

= Problem with DNS Client Cache CNAME TTL =

Article ID: 276324

Article Last Modified on 2/21/2007

-

APPLIES TO


 * Microsoft Windows 2000 Service Pack 1
 * Microsoft Windows 2000 Service Pack 2
 * Microsoft Windows 2000 Advanced Server
 * Microsoft Windows 2000 Advanced Server
 * Microsoft Windows 2000 Service Pack 1
 * Microsoft Windows 2000 Service Pack 2

-



This article was previously published under Q276324



SYMPTOMS
Resource records that are stored in the DNS Client cache may not expire at the proper time.



CAUSE
This problem can occur because when a CNAME record is cached, the Windows 2000 DNS Client resolver groups the CNAME record and its associated A records as a single unit in the DNS Client resolver cache. All records in this grouping unit are assigned the Time To Live (TTL) value of the CNAME record. Because of this, if the A records have a smaller TTL than the CNAME, they will continue to be cached for the lifetime of the CNAME.



RESOLUTION
To resolve this problem, obtain the latest service pack for Windows 2000. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

260910 How to Obtain the Latest Windows 2000 Service Pack

The English version of this fix should have the following file attributes or later:

  Date         Time     Version          Size    File name -  5/31/2001    11:13p   5.0.2195.3663  501,520   Lsasrv.dll (56-bit) 5/31/2001   03:30p   5.0.2195.3649  354,576   Advapi32.dll 5/31/2001   03:31p   5.0.2195.3649  135,440   Dnsapi.dll 5/31/2001   03:31p   5.0.2195.3649   94,992   Dnsrslvr.dll 5/31/2001   03:37p   5.0.2195.3649  519,440   Instlsa5.dll 5/31/2001   03:31p   5.0.2195.3649  142,608   Kdcsvc.dll 5/30/2001   02:55p   5.0.2195.3649  209,008   Kerberos.dll 5/29/2001   09:26a   5.0.2195.3649   69,456   Ksecdd.sys 5/29/2001   09:26a   5.0.2195.3649  501,520   Lsasrv.dll 5/29/2001   09:26a   5.0.2195.3649   33,552   Lsass.exe 5/31/2001   03:31p   5.0.2195.3649  306,448   Netapi32.dll 5/31/2001   03:31p   5.0.2195.3649  357,136   Netlogon.dll 5/31/2001   03:31p   5.0.2195.3652  908,560   Ntdsa.dll 5/31/2001   03:31p   5.0.2195.3649  382,736   Samsrv.dll

After this fix is successfully applied, the DNS Client resolver will use the lowest TTL returned and assign it to all RRs in that group.



STATUS
Microsoft has confirmed that this is a problem in Microsoft Windows 2000. This problem was first corrected in Windows 2000 Service Pack 3.



MORE INFORMATION
For additional information about how to install Windows 2000 and Windows 2000 hotfixes at the same time, click the article number below to view the article in the Microsoft Knowledge Base:

249149 Installing Microsoft Windows 2000 and Windows 2000 Hotfixes

Additional query words: kbDirServices

Keywords: kbbug kbfix kbwin2000presp3fix kbqfe kbwin2000sp3fix kbenv kbdirservices kbhotfixserver KB276324

-

[mailto:TECHNET@MICROSOFT.COM Send feedback to Microsoft]

© Microsoft Corporation. All rights reserved.