Understanding and Performing Feature Delegation

Feature delegation is a touchy subject in IIS 7. On one hand, you control the overall flexibility of the server with this feature. Web site administrators must have a feature delegated to them before they can use it. On the other hand, every feature you delegate to Web site administrators increases the risk of security, reliability, and even speed problems. You must delegate some features, and the default IIS setup provides these features to Web site administrators by default. Some features you don't want to delegate for any reason because they could cause significant problems. To access the Feature Delegation pane, choose the Web server entry in the Connections pane and double-click the Feature Delegation icon.

The settings you delegate depend on the kind of applications you plan to run on the server. For example, if you don't plan to run CGI applications, you should remove the delegation from that feature because setting up CGI incorrectly can cause all kinds of security and reliability problems. In addition, CGI applications tend to use resources inefficiently. A Web site administrator could decide to install and use a CGI application without permission when you provide the required delegation. The following sections describe various forms of feature delegation.

Changing the overall level of delegation

In most cases, you need to make some feature delegation choices as part of the initial server setup. Whenever you highlight one of the features in the list, the Actions pane choices change to reflect the levels of delegation you can provide for that feature. Simply click the link in the Actions pane that reflects the level of delegation you want to provide for that feature.

Changing the custom delegation for a Web site

In some cases, one Web site requires different functionality from others on your server. When this situation occurs, you can create a custom delegation setup for that Web site. To perform this task, click Custom Site Delegation in the Actions pane. You see the Custom Site Delegation window, where you can choose the Web site you want to manage. After you select the Web site, you can highlight individual features as you normally do and choose the level of delegation you want to provide in the Actions pane.

Correcting delegation mistakes

It's possible that you'll assign the wrong delegation to a particular feature or to the Web site or server as a whole. When you find that the delegation setup you created is a hopeless mess, click Reset All Delegation in the Actions pane. Using this option returns IIS 7 to its default configuration. Of course, you have to start delegating features from scratch.

When you find that you modified a particular feature incorrectly but don't remember the setting you should use, highlight that feature in the list and click Reset to Inherited in the Actions pane. IIS 7 returns that feature to the state it inherited originally.