A server architecture that houses multiple server modules ("blades") in a single chassis. It is widely used in datacenters to save space and improve system management. Either self-standing or rack mounted, the chassis provides the power supply, and each blade has its own CPU, memory and hard disk. Redundant power supplies may be an option. Blade servers generally provide their own management systems and may include a network or storage switch. Contrast with blade PC.|
With enterprise-class blade servers, disk storage is external, and the blades are diskless. This approach allows for more efficient failover because applications are not tied to specific hardware and a particular instance of the operating system. The blades are anonymous and interchangeable. See blade and processor area network.
Blade servers are widely used in datacenters to save space and ease systems management. This earlier ProLiant unit from HP has redundant power supplies and holds 20 blades in 3U of rack space. The exposed blade on the left is a complete server with hard disk. (Image courtesy of Hewlett-Packard Company.)
The BladeFrame from Egenera supports up to 24 blades, each with four Xeon processors. The entire system is managed with Egenera's PAN Manager software via a Web browser. In this picture, one blade is being replaced. (Image courtesy of Egenera, Inc., www.egenera.com)