This snippet of Puppet code, designed for use with the Puppet Labs apt module, configures an Ubuntu system to use the Ubuntu Cloud Archive.

apt-source-ubuntu-cloud

apt::source { 'ubuntu-cloud':
  location          =>  'http://ubuntu-cloud.archive.canonical.com/ubuntu',
  repos             =>  'main',
  release           =>  'precise-updates/grizzly',
  include_src       =>  false,
  required_packages =>  'ubuntu-cloud-keyring',
}