How to update my rails 3.0.0 beta 4 app to rails 3.0.0 RC and eventually to Rails 3?

Answer 1

gem install bundler --pre
bundle install

Answer 2

You may want to check out upgrading Rails from beta4 to RC. It's mentioning changes to Bundler and to your app's files (like config/* and Rakefile).

Answer 3

This screencast came out in the last couple of days that walks through many of the changes.

Answer 4

There are also important changes to bundler usage (like the default install location is now system-wide, not local). Yehuda gives a great overview of best practices:

Deployment
When deploying, we strongly recommend that you isolate your gems into a local path (using bundle install path --disable-shared-gems). The final version of bundler will come with a --production flag, encapsulating all of the best deployment practices.

For now, please follow the following recommendations (described using Capistrano concepts):

1. Make sure to always check in a Gemfile.lock that is up to date. This means that after modifying your Gemfile, you should ALWAYS run bundle install.

2. Symlink the vendor/bundle directory into the application’s shared location (symlink release_path/current/vendor/bundle to release_path/shared/bundled_gems)

3. Install your bundle by running bundle install vendor/bundle --disable-shared-gems

http://bit.ly/bh3lNw