Controlling boot behavior with cloud-init

Cloud-init is a multi-distribution, open-source package developed by Canonical that handles the early initialization of a server running Linux. The behavior of cloud-init can be configured using customer-supplied user data. User data is supplied via a config file written in cloud-config specific syntax that contains directives on how cloud-init should behave.

More information about cloud-init is available in the cloud-init documentation.

In the Rackspace cloud, cloud-init is responsible for handling some of the server setup actions traditionally performed by the nova-agent. This varies from image to image, but currently cloud-init handles the disk expansion and partitioning for Linux PVHVM images.