This document outlines several problems that you may experience with your Ruby installation.
Ruby on Rails uses its own web server, which must run on an alternate port. This causes an issue if you run a firewall on your system.
Ensure that you have opened each Ruby application's port in your firewall. We recommend that you only open the range of ports that are necessary to access each application (for example, if you run six Ruby applications, open ports 12001 through 12006 on the firewall).
Occasionally, the RubyGems repository is unavailable. If the RubyGems repository is unavailable during the installation process, run the /usr/local/cpanel/scripts/installruby script again.
For more information, read the Ruby documentation.
To troubleshoot Mongrel-specific errors, review the /log/mongrel.log file.
If the errors indicate uninstalled gems, install them with the gem install name command, where name represents the gem name.
If the errors indicate the wrong version of gems, run the gem uninstall command, and then reinstall the correct gem version.
Run this command from the Ruby on Rails application's base directory as the user who owns the Ruby application.
Use Ruby's built-in tools to diagnose the problem.
cPanel & WHM uses the standard set of Ruby on Rails tools.
Check the /usr/local/cpanel/logs/error_log file and the /log/mongrel.log file for Ruby-related errors.
Check for application-specific errors in the /log/mongrel.log file.