This plugin enables use of Atlassian Crowd as an authentication source. Crowd is a commercial identity management and Single Sign-On (SSO) application.
To configure the plugin, you first need to create a new application in Crowd. http://confluence.atlassian.com/display/CROWD/Managing+Applications has more information on how to configure applications in Crowd.
Be sure to also allow connections to Crowd from the server Hudson runs on. As of the current (1.5.1) release, this must be done per IP address; vote for http://jira.atlassian.com/browse/CWD-84 to allow this to be configured on a block basis.
Once you have the application configured in Crowd, you can enable Crowd-based security in Hudson on the Manage Hudson page. Enter the URL of the Crowd's servers endpoint (will typically be /crowd/services/ or /services/) as well as the application name and password you configured in Crowd.
This plugin requires Hudson version 1.318 or higher. It has primarily been tested against Crowd version 1.6.
Crowd has a setting, which can be set per application, called "Lower Case Output". If you have, e.g., a group called "SystemAdministrators", and "Lower Case Output" is set, then Crowd will pass this group name to Hudson as "systemadministrators". To fix this, either: