This lists the cloud providers and the support available:
Rackspace Cloud is the first (and currently only) provider supported by Silver Lining.
To use Silver Lining you must sign up for an account through their website. You should sign up for “Cloud Servers” and “Cloud Files”. There’s no initial fee, and the cost for experimenting with Silver Lining will be less than a dollar as long as you don’t forget to take down the servers you create to experiment. You’ll have to have a credit card, and Rackspace Cloud will call you to confirm your account before you can use it.
Once you have logged in go to Your Account > API Access to view or create your API key. Silver Lining needs to know your username and API key, which it will ask you for when you first start the command.
You don’t need to use commands like silver create-node to make use of Silver Lining. If you have a machine with a fresh install of Ubuntu Jaunty (or Karmic) then you can use silver setup-node to configure the machine and silver update to deploy applications. It’s harder to test things without the ability to create and destroy servers on demand, but the basic infrastructure is not really dependent on that.
Don’t use this on a server you want to keep! silver setup-node is not aggressive in modifying the server, but it doesn’t particularly keep track of what it does, nor is there any reason it should. Also if you have local modifications on the server, those modifications can be lost; all updates are done with the assumption that it’s being given a bare Ubuntu installation to work with.
Silver Lining is built on libcloud. libcloud abstracts over the API of quite a few cloud providers. Any of these providers should be a possible platform for Silver Lining; the basic abstractions already exist, it just needs some testing. The only thing that’s currently really Rackspace-specific is that on node creation some files are uploaded – not a complete set, mostly just /root/.ssh/authorized_keys2. This is built in to some other APIs (e.g., I believe EC2 node creation automatically sets up authorized_keys). It would require a bit of abstraction as a result.
The best way to try a new provider is to fork the Silver Lining repository, try it out, and make what patches are necessary – probably to the routine that creates ~/.silverlining.conf (silverlining.createconf), silver create-node (silverlining.commands.create_node), and maybe silver setup-node (silverlining.commands.setup_node) – though I expect setup-node will be fine.