Originating Author: David Floyer

Commodity hardware is cheap, but inherently unreliable; blades are no exception. The biggest causes of failure are complex operating procedures and commodity operating systems and disks. Virtualization of blade environments can mitigate these problems.

The key is complete separation of storage from processors and ensuring there is no fixed association of an application with a physical server. By using virtualization engines such as Ardence and VMWare, system software can be centralized and version control managed. This means OS failures can benefit from a central repository of OS versions enabling super-fast OS problem resolution by, for example, reverting to a previous version of an OS. By virtualizing the storage, data can be striped across multiple arrays so that no single disk failure will cause applications to crash. By separating storage from server, all recovery files such as journals which preserve the state of an application can be accessed by other servers, which minimizes the time to recover.

Action item: Configure blades with storage external to the servers and ensure the servers have no fixed association with applications. Focus blade virtualization projects on creating simple robust environments, not on saving processor cycles.