I have a VPS running debian lenny, and I currently am running a Ruby on Rails application that uses Rails 2.3.5. This application works fine by itself, and uses Apache 2.2 with mod_rails.
I would like to additionally install another Ruby on Rails application that uses Rails 3.0.6.
However, I am concerned that there may be a conflict in how each RoR application refers to the different rails installations, and I definitely do not want to break anything in the already-working application by installing the new one.
Is there a sure-fire method of installing these two versions of Rails side-by-side on the same server, safely?
mod_rails (i.e. Passenger) will just take care of this for you.
http://www.modrails.com/documentation/Users%20guide%20Apache.html#_installing_multiple_ruby_on_rails_versions
You can have multiple rails gems installed, and your application's config.rb will define which version of rails to use.