Installing CAS

Drupal Version

There are two components needed to add CAS support to a Drupal website: the phpCAS Library, and two supporting Drupal modules.

phpCAS Library

This library is only needed for Drupal 7.  If you are installing the CAS module for Drupal 8, you can skip this section.

  1. Download and install the current, stable version of the phpCAS Library.  As of early 2017, the current version was phpCAS 1.3.4 – if you are using and older version, you should consider upgrading as soon as possible to get the latest security patches.
  2. Install it under the sites/all/libraries/ directory of your Drupal site.  Rename the top level directory to CAS so that you have the CAS.php file inside of sites/all/libraries/CAS/

Drupal Modules

You will need to configure CAS to talk to the Georgia Tech CAS service.

  1. Log into the special original user account (user #1) that you setup when creating your Drupal site.  This is the main administrative account that has full power over everything in your site.  If this account is the same as someone's GT Account Username, you should rename the account to something else (good names are "root" or "admin", which make it easy to identify the account later on.
  2. For Drupal 7, download and install the Libraries and CAS modules into your Drupal site's sites/all/modules/ directory, or if your site supports it, install them via the Install Module option in the Modules section of your site's administrative controls.
  3. For Drupal 8, download and install the External Authentication and CAS modules into your Drupal site's sites/all/modules/ directory, or if your site supports it, install them via the Install Module option in the Modules section of your site's administrative controls.
  4. Go to the Modules page of your site's administrative controls and enable (turn on) both modules.  Once you have enabled these modules DO NOT LOG OUT OF THE SITE until you have finished the remaining steps.  Otherwise, you will find yourself locked out of your site!
  5. For Drupal 7 only, go to the Permissions page of your site's administrative controls (found under the People section), and make sure that the following permissions are enabled for the highest level user role in your site (commonly "administrator", or for sites using the GT Profile, "super administrator") (Don't forget to save your changes!) :
    • CAS -> Administer CAS
    • User -> Administer Permissions
    • User -> Administer Users
  6. Go to the CAS settings page of your site's administrative controls (found under the Configuration -> People section) and configure your CAS settings (see Drupal version specific links below for more details).
  7. Add a new user to the site with the username and "CAS username" both being the same as your GT Account Username.  Set the other fields as needed (enter a random value for the password field) and give the account the highest access level available (usually 'administrator').  Don't forget to save the new account.
  8. In a different web browser from the one in which you are currently using (or via your browser's private browsing feature), browse to your Drupal site and verify that you can login with your personal GT Account Username and password.  You should not see the normal Drupal login prompt - if you are prompted at all, you should be taken to the Georgia Tech Login service and then brought back to the Drupal site after you've successfully logged in to your GT Account.
  9. Repeat step #7 above for each user who should have access to the site, setting the access level as appropriate for the individual user.

CAS Configuration Guides