System-wide rvm install on Ubuntu

Here are the steps I used to install RVM system wide on a Ubuntu 10.04.1 LTS node on Amazon EC2, using one of the Canonical AMIs. These set up the primary user as 'ubuntu', requiring you to sudo for system commands. I could install rvm under that user but installing System-Wide is recommended.

This HOWTO is based on the RVM page http://rvm.beginrescueend.com/deployment/system-wide/. But I find the RVM site documentation makes a few assumptions with regard to commands.

1: Install git if you don't already have it

$ sudo apt-get install git-core

2: Download RVM

$ sudo bash < <( curl -L http://bit.ly/rvm-install-system-wide )

This creates /usr/local/rvm and the group 'rvm'

3: Add each user to group rvm

$ sudo usermod -aG rvm ubuntu

4: Add startup lines to each user's .profile

[[ -s '/usr/local/lib/rvm' ]] && source '/usr/local/lib/rvm'

5: Add this line to /etc/rvmrc (may not be necessary)

$ echo "export rvm_path=/usr/local/rvm" > /etc/rvmrc

6: Use rvm as a user - best to logout/login first to make sure you get all the paths etc setup

$ rvm list
$ rvm package install zlib   ( I needed this to get install to work )
$ rvm install 1.9.2 --with-zlib-dir=/usr/local/rvm/usr

Note that you use rvm as a regular user, not via sudo, even though this is a system wide install.