IMS: Smtpsvc Queue Processing Is Slow When DNS Lookup Fails

Last reviewed: February 3, 1998
Article ID: Q168108
The information in this article applies to:
  • Microsoft Commercial Internet System, version 1.0

SYMPTOMS

The Internet Mail Server (IMS) may process mail slowly resulting in a backup of mail in the mail queue as well as in the pickup directories. The queue directory will contain a large number of .rtr files which indicates that multiple Domain Name Service (DNS) retries have occurred.

CAUSE

Excessive DNS query failures cause mail processing to perform slowly because IMS continually attempts to resolve the names against the DNS. The DNS lookup attempts use a critical section to ensure mutual exclusion when running the DNS lookup code. This causes all other queue processing that requires DNS resolution to stop until the current DNS lookup is complete.

RESOLUTION

Smtpsvc.dll was modified to resolve contributing issues with the handling of DNS MX lookups, and the handling of DNS lookup retries.

STATUS

Microsoft has confirmed this to be a problem in Microsoft Commercial Internet System version 1.0. A supported fix is now available, but has not been fully regression- tested and should be applied only to systems experiencing this specific problem. Unless you are severely impacted by this specific problem, Microsoft recommends that you wait for the next Service Pack that contains this fix. Contact Microsoft Technical Support for more information.


Additional query words: 9124 15640
Version : 1.0
Platform : winnt
Hardware : ALPHA x86
Issue type : kbbug
Solution Type : kbfix


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.

Last reviewed: February 3, 1998
© 1998 Microsoft Corporation. All rights reserved. Terms of Use.