Cannot Disable HTTP KeepAlives for HTTP/1.1 Clients

ID: Q195179

The information in this article applies to:

Microsoft Internet Information Server version 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 :
Version : WINNT:4.0
Platform : winnt
Issue type : kbprb