All of the following commands need to be run as root or with the use of sudo:

First, make sure Ruby is installed:

root@host:[~]$ /scripts/installruby

Next, install Passenger:

root@host:[~]$ gem install passenger

Then set the paths to Apache and the Apache dev headers and run the installer:

root@host:[~]$ APXS2=/usr/local/apache/bin/apxs PATH=$PATH:/usr/local/apache/bin passenger-install-apache2-module
Welcome to the Phusion Passenger Apache 2 module installer, v2.2.5.

This installer will guide you through the entire installation process. It
shouldn't take more than 3 minutes in total.

Here's what you can expect from the installation process:

1. The Apache 2 module will be installed for you.
2. You'll learn how to configure Apache.
3. You'll learn how to deploy a Ruby on Rails application.

Don't worry if anything goes wrong. This installer will advise you on how to
solve any problems.

Press Enter to continue, or Ctrl-C to abort.

Hit enter and the installer will compile the Apache 2 module. If this is successful you will get a message with directions for modifying the Apache conf:

The Apache 2 module was successfully installed.

Please edit your Apache configuration file, and add these lines:

LoadModule passenger_module /usr/lib/ruby/gems/1.8/gems/passenger-2.2.5/ext/apache2/mod_passenger.so
PassengerRoot /usr/lib/ruby/gems/1.8/gems/passenger-2.2.5
PassengerRuby /usr/bin/ruby

After you restart Apache, you are ready to deploy any number of Ruby on Rails
applications on Apache, without any further Ruby on Rails-specific
configuration!

Press ENTER to continue.

Copy the configuration directives and place them in /usr/local/apache/conf/includes/pre_main_global.conf. Do not directly edit the httpd.conf!

These are the lines that should be added (with server-specific version numbers):

LoadModule passenger_module /usr/lib/ruby/gems/1.8/gems/passenger-2.2.5/ext/apache2/mod_passenger.so
PassengerRoot /usr/lib/ruby/gems/1.8/gems/passenger-2.2.5
PassengerRuby /usr/bin/ruby

Add the following to the httpd.conf (passenger docs):

PassengerResolveSymlinksInDocumentRoot on

Run the httpd.conf config distiller to save these changes:

root@host:[~]$ /usr/local/cpanel/bin/apache_conf_distiller --update
Distilled successfully

Then rebuild the httpd.conf using the cPanel rebuild script. Stop and correct any errors before restarting Apache:

root@host:[~]$ /scripts/rebuildhttpdconf
Built /usr/local/apache/conf/httpd.conf OK

Restart Apache and verify Passenger is installed by running this command:

root@host:[~]$ apachectl -t -D DUMP_MODULES

Check for ‘passenger_module (shared)’.

By default, RailsAutoDetect is on so it will detect a directory that is a Rails application. If this is off, you will need to add a custom vhost configuration to let Apache know to load Passenger for a particular site. To do this add the following to the site’s vhost container:

RailsBaseURI /

(or whatever URI is the base of the application)

Directions for adding custom directives to a vhost in cPanel: Add Custom Apache Directives to a vhost in cPanel

If the Rails application will be the root of the site, you will need to create a symlink from the Rails application’s public directory to /home/[username]/public_html.