rvm部署rails3和ruby192

1. Installing RVM

$ sudo gem install rvm  
$ rvm-install 

Finally put this lines in your .bash_profile or .bashrc:

if <a href="/pages/s-home-rvm-scripts-rvm?create=true&title= -s $HOME/.rvm/scripts/rvm " class="missing_page"> -s $HOME/.rvm/scripts/rvm </a> ; then 
        source $HOME/.rvm/scripts/rvm
fi

Restart your terminal, RVM should be working by now.
2. Installing ruby into your RVM

$ rvm install 1.8.7

3. Setting up RVM to use your specific ruby version

$ rvm use 1.8.7 --default  

4. Installing rails 2 and rails 3 inside different gemsets

Rails 2:

$ rvm gemset create rails2
$ rvm use 1.8.7@rails2 --default
$ gem install rails

Rails 3:

$ rvm gemset create rails3
$rvm use 1.8.7@rails3 --default
$ gem install rails

5. Switching between different rails versions

Switching to rails 2:

$ rvm use 1.8.7@rails2
$ rails -v
Rails 2.3.5  

Switching to rails 3:

$ rvm use 1.8.7@rails3
$ rails -v
Rails 3.0.0