Check Out the Racks
In a server blade approach, the rack is best place to start when comparing systems. Although a company will buy far fewer racks than blades, the rack is the fundamental framework, and its physical properties say much about the operation and benefits of the system designed for it.
For example, consider the system offered by Egenera: The basic rack consists of a 24 x 30 x 84 inch chassis that can hold up to 24 two-way or four-way processing blades. Egenera also offers storage, integrated switches, controllers, and cluster connection buses. The company considers its blade system a suite of processor, storage, and network capabilities in a rack. BladeFrame is tied together with Egenera’s own Processing-Area Network (PAN) manager software that lets the system administrator configure, control, and monitor the blades from a single location. The system is priced starting at about $250,000.
When checking out the racks, key things to look for are rack size, density (the number of blades supported), power consumption per loaded rack, heat generated, cooling facilities, cable connections, switching options, and system coordination features to distinguish products. One important caveat: In most cases the match of blade and rack is proprietary. Thus, it is rare to be able to operate one company’s blade in another company’s rack.
Obviously, this makes choice of rack and vendor a long-term commitment.