Using a the Xen Hypervisor to Supercharge OS Deployment
Hypervisor technology presents some promising opportunities for optimizing Linux deployment. By isolating a server's unique properties into a set of patches to initialization scripts and other selected files, deployment of a new server will be demonstrated to occur in a few seconds by creating a new Xen domain, re-using an existing file system image and applying patches to it during domain initialization. To capture changes to a server's configuration that occur while it is running, the paper discusses the potential of copy-on-write file systems to hold changes to selected files. By separating the initialization and file data that make a linux server instance unique, that data can be stored and retrieved in a number of ways. The paper demonstrates how to store and retrieve different initialization patches over the network and integrate these capabilities into the Xen tools. Potential uses for the techniques demonstrated in the paper include capacity on demand, and new methods of provisioning servers and workstations.