The maximum queue length for HTTP.sys for each IIS 8.5 website must be explicitly configured.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-214489	IISW-SI-000256	SV-214489r766889_rule		Medium

Description
In order to determine the possible causes of client connection errors and to conserve system resources, it is important to both log errors and manage those settings controlling requests to the application pool.

STIG	Date
Microsoft IIS 8.5 Site Security Technical Implementation Guide	2022-06-17

Details

Check Text ( C-15698r766887_chk )
If this IIS 8.5 installation is supporting Microsoft Exchange, and not otherwise hosting any content, this requirement is Not Applicable. Open the IIS 8.5 Manager. Perform for each Application Pool. Click the "Application Pools". Highlight an Application Pool to review and click "Advanced Settings" in the "Actions" pane. Scroll down to the "General" section and verify the value for "Queue Length" is set to 1000. If the "Queue Length" is set to "1000" or less, this is not a finding.

Check Text ( C-15698r766887_chk )

If this IIS 8.5 installation is supporting Microsoft Exchange, and not otherwise hosting any content, this requirement is Not Applicable.

Open the IIS 8.5 Manager.

Perform for each Application Pool.

Click the "Application Pools".

Highlight an Application Pool to review and click "Advanced Settings" in the "Actions" pane.

Scroll down to the "General" section and verify the value for "Queue Length" is set to 1000.

If the "Queue Length" is set to "1000" or less, this is not a finding.

Fix Text (F-15696r766888_fix)
Open the IIS 8.5 Manager. Click the "Application Pools". Highlight an Application Pool to review and click "Advanced Settings" in the "Actions" pane. Scroll down to the "General" section and set the value for "Queue Length" to "1000" or less. Click "OK".