Packages required for ansible:
a Note for managed nodes: (from: http://ansible.cc/docs/gettingstarted.html)
Ansible’s “raw” module (for executing commands in a quick and dirty way) and the script module don’t even need that. So technically, you can use Ansible to install python-simplejson using the raw module, which then allows you to use everything else. (That’s jumping ahead though.)
I like that!
I am a minimalist. So I use this feature to admin minimally installed Solaris nodes from an ansible node. This is a minimalistic installed Ubuntu. It includes packages required already. On my managed Solaris nodes there is no way to login as root remotely (forbidden in the SSH config), only admins with their own accounts can use SSH to login and then sudo to root (assumed that they can do that with a good sudo config). So I like that! You do not need much, you live minimalistic, elastic AND secure! All in one!
Another extremely flexible way is to allow direct remotely root logins over SSH and then use public keys of your admins in ~root/.ssh/authorized_keys on target nodes you want to manage. It is also secure enough.