Salt cloud is a public cloud provisioning tool. Salt cloud is made to integrate Salt into cloud providers in a clean way so that minions on public cloud systems can be quickly and easily modeled and provisioned.
Salt cloud allows for cloud based minions to be managed via virtual machine maps and profiles. This means that individual cloud VMs can be created, or large groups of cloud VMs can be created at once or managed.
Virtual machines created with Salt cloud install salt on the target virtual machine and assign it to the specified master. This means that virtual machines can be provisioned and then potentially never logged into.
While Salt Cloud has been made to work with Salt, it is also a generic cloud management platform and can be used to manage non Salt centric clouds.
Some quick guides covering getting started with Amazon AWS, Rackspace, and Parallels.
The core configuration of Salt cloud is handled in the cloud configuration file. This file is comprised of global configurations for interfacing with cloud providers.
Salt cloud works via profiles and maps. Simple profiles for cloud VMs are defined and can be used directly, or a map can be defined specifying a large group of virtual machines to create.
Once a VM has been deployed, a number of actions may be available to perform on it, depending on the specific cloud provider.
Depending on your cloud provider, a number of functions may also be available which do not require a VM to be specified.
Salt cloud extensions work in a way similar to Salt modules. Therefore extending Salt cloud to manage more public cloud providers and operating systems is easy.