Problem with DNS Client Cache CNAME TTL (276324)


The information in this article applies to:

  • Microsoft Windows 2000 Server SP1
  • Microsoft Windows 2000 Server SP2
  • Microsoft Windows 2000 Advanced Server SP1
  • Microsoft Windows 2000 Advanced Server SP2
  • Microsoft Windows 2000 Professional SP1
  • Microsoft Windows 2000 Professional SP2
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

Modification Type:MinorLast Reviewed:9/26/2005
Keywords:kbHotfixServer kbQFE kbbug kbDirServices kbenv kbfix kbWin2000PreSP3Fix kbWin2000sp3fix KB276324
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