RVM and RubyGems versions


You would like to upgrade your rubygems version from 1.8.17 to the latest version 2.0.7 for example.


You can upgrade to a specific or the latest gem version and relate that to a specific rvm ruby that you have installed.
So if for example you have ruby-1.9.3-p327 and ruby-2.0.0-p247, you can have different gem version (or the same if you want) for each ruby version.

To upgrade to the latest one in the ruby-2.0.0-p247 for example you could do the following:

rvm list
rvm use ruby-1.9.3-p327
gem -version
rvm use ruby-2.0.0-p247
gem --version
gem update --system
gem --version
rvm use ruby-1.9.3-p327
gem --version

Upgrading your Rails 3.0.3 application

After the announcements in the previous posts about the security vulnerabilities in Rails 3.0.3, you would like to update your application and deploy with the latest 3.0.4 version.


  • Change your Gemfile to replace
    gem 'rails', '3.0.3'
    gem 'rails', '3.0.4'
  • Run:
    bundle update rails
  • Remove the old gems by using:
    git status
    and then
    git rm name_of_3.0.3_gem
  • Add the new gems to your git
    git add vendor/cache
  • Check in to your repository the new files
    git commit vendor/cache -m 'upgrade to rails 3.0.4'
  • Make sure that you also check in both your Gemfile and Gemfile.lock into your git repository
    git commit Gemfile Gemfile.lock -m 'update Gemfiles to use 3.0.4'
    otherwise when you try to deploy you will see the error:
    You have modified your Gemfile in development but did not check the resulting snapshot (Gemfile.lock) into version control
  • push everything to your git repository:
    git push
  • Deploy your application with capistrano as usual:
    cap deploy
  • Your new gems for 3.0.4 should be installed on the share/bundle folder

Freezing rails to an older version using gems

You want to deploy to a shared host (dreamhost) that has a later version of rails from the one you have developed your application.
You also have a later version installed in your development pc,and using rake rails:freeze:gems uses the latest one and not the one you want.

Use the following to freeze the specific version you want, and by using your gems you have installed:
rake rails:freeze:gems VERSION=2.3.2