KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q195179: Cannot Disable HTTP KeepAlives for HTTP/1.1 Clients

Article: Q195179
Product(s): Internet Information Server
Version(s): WINNT:4.0
Operating System(s): 
Keyword(s): 
Last Modified: 07-MAY-1999

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

- Microsoft Internet Information Server 4.0 
-------------------------------------------------------------------------------

SYMPTOMS
========

HTTP/1.1 client connections are not closed, even if the Allow HTTP KeepAlives
check box is not selected in the Web site's properties in Microsoft Management
Console (MMC).

CAUSE
=====

This behavior occurs because the Allow HTTP KeepAlives check box applies only to
HTTP/1.0 clients that connect to the IIS server.

RESOLUTION
==========

This behavior is by design.

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

The "Section 8.1.2.1 Negotiation" section of RFC2068 states the following:

  In case the client does not want to maintain a connection for more than
  that request, it SHOULD send a Connection header including the
  connection-token close.

Sections 8.1.2.1 and 19.7.1 both discuss backwards compatibility for previous
HTTP versions and state that persistent connections must be explicitly
negotiated.

The AllowKeepAlives feature is only valid in the following scenarios:

If you clear the Allow HTTP KeepAlives check box on the server and use an
HTTP/1.0 client that tries to establish a persistent connection, the server
sends a close.

If you select the Allow HTTP KeepAlives check box on the server and use an
HTTP/1.0 client that tries to establish a persistent connection, the server
honors the request for persistence.

======================================================================
Keywords          :  
Technology        : kbiisSearch kbiis400
Version           : WINNT:4.0
Issue type        : kbprb

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

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.