Blade servers are very alluring to CIOs -- they're space-saving, fully functional units that deploy easily, reduce power usage and work smoothly with leading virtualization software from companies like VMware Inc. All of which makes blades perfect for server consolidation … and for saving power and money.
Ed Sherman, network services manager for Kitsap County, Wash., said he expects to save taxpayers about $300,000 by using blade servers instead of rebuilding his server room to house regular servers. Sherman and his staff are consolidating 60 standard servers (half the room's total number of servers) into five Hewlett-Packard Co. blades running VMware's virtualization software. The county plans to buy four more HP blades for failover and disaster recovery purposes.
"We have zero floor space left for expanding the server room, and we can't get any more electrical power in here," Sherman said. "Blades are the perfect solution for us. They give us room to grow, without requiring more power." The blades and software will cost about $100,000.
"Virtualized blades also give us a fantastic platform for our disaster recovery plan," he said. "They will give us the ability to be up and running within minutes of any disaster."
Benefits of blades
Reducing server sprawl is the main reason behind users' adoption of blades, according to TheInfoPro Inc.'s Wave 4 Server Study. Sixty-six percent of enterprise respondents to the study believe that by 2009, blades will make up more than 50% of all new server units acquired.
Blades are smaller than standard rack-mounted servers, which are stacked horizontally, much like a pile of pizza boxes. Blades also fit into racks, but they're packed vertically, similar to books on a shelf, and make better use of space.
A big benefit of blade servers is they plug into a backplane that enables them to share vital resources -- power, cooling and networking connections -- that rack-mounted servers don't share.
Downside to blade servers
Blades are not without their downsides, of course.
The biggest downside is the per-unit cost of a blade -- prices start near $2,000 and rise precipitously. Of course, if you can virtualize 10 or more standard servers into one blade unit, the unit cost is put into context.
Another downside can be less-than-perfect cooling of the blade enclosure. This was more of an issue when blades first appeared, but it's less so nowadays with the prevalence of well-engineered units from Dell Inc., HP, IBM and Sun, some of the most prominent players in the market.
Still, many of today's data centers aren't designed to hold numerous servers packed tightly together. Adding dozens or hundreds of blades will require IT people to ensure they have sufficient air conditioning power and that their data center floors can handle the weight of numerous racks crammed with dozens of blades from top to bottom.
Another downside to blades is the proprietary nature of the hardware, said Steve Kaplan, president of Access Flow Inc., a Sacramento, Calif.-based solution provider that specializes in VMware virtualization.
"I never recommend blades to any of my clients," Kaplan said. "I think the proprietary nature of blade technology is too limiting. It ties customers to one vendor's boxes, interfaces and firmware upgrades. If space is not an issue, I see no reason why a company would want to choose a blade server."
The proprietary nature of HP's blades does not bother Sherman. "The solution works extremely well," he said. "It will allow us to scale up for a long time to come."
Herman Mehling is a freelance writer based out of San Anselmo, Calif. He can be reached at hermanmehling@sbcglobal.net.
