Blade servers were created a few years ago as a solution for the cabling and integration management issues of clustered systems. They're built using identical server modules mounted as plug-in "blades." Typically, a couple of HDDs are included in each blade.
A set of blades is mounted in a blade chassis, with redundant power supplies. Intra-cluster networking is provided by a built-in Ethernet switch. These configurations make for a compact, ready-to-use cluster.
The blade server concept began with the idea of having low-cost, small-form-factor servers in a cabinet. Configurations of 12 servers in a 3U cabinet looked like the sweet spot, and the aim was to cut space, power, and acquisition cost for ISPs servicing the LAMP market.
The concept of inexpensive small-blade servers got lost in the post-9/11 crash of the industry. But blades survived as larger modules with more memory. These units can't be described as inexpensive. Some were even made of anodized gold to add a bit of class (and price).
The blade server continues today with a reasonable market size. Increasingly, densely packed server designs have nibbled away at the market, and the advent of Google-class CSPs and containerized data centers has renewed the emphasis on smaller footprints and lower costs.
Read the rest of this article on Network Computing.Jim O'Reilly was Vice President of Engineering at Germane Systems, where he created ruggedized servers and storage for the US submarine fleet. He has also held senior management positions at SGI/Rackable and Verari; was CEO at startups Scalant and CDS; headed operations at PC ... View Full Bio