Đặng Phương Nam

Phusion Passenger (commonly shortened to Passenger or referred to as mod_passenger) is an application server and it is often used to power Ruby sites. Its code is distributed in form of a Ruby gem, which is then compiled on the target machine and installed into Apache as a module.

For multiple database connection, you need to add the following codes to the database.yml file. Here, I am giving the example of connecting two databases from a rails application

Specified 'mysql2' for database adapter, but the gem is not loaded. Add `gem 'mysql2'` to your Gemfile (and ensure its version is at the minimum required by ActiveRecord).