Blade servers may be able to make your data center really easy to manage. And that's not all. They can save you space, cabling, power and more.
Sound like a good deal? Well, many people think so. And if you move to Linux on a blade server setup, you have an additional benefit: You can access the full panoply of open source software that's available for zero licensing cost.
So, you'll save money as well. "I haven't done the true ROI calculations," said Tom Burns, director of technology for CORE Feature Animation, a Toronto company engaged in providing the computer-generated animation for an upcoming feature film. "But my gut tells me that using Linux with blades in a Linux cluster costs less. You can find the people who know the OS and the management tools and who can run your operation. Everyone in the 3-D animation world has moved from Crays, then to SGI [Silicon Graphics Inc.] and now to the blade concept with Linux as the operating system of choice."
That's a pretty strong endorsement for something that until about a year ago hadn't even been heard of. But blade servers are really coming on strong, because of all these listed advantages, according to IBM's director of eServer BladeCenter marketing Tim Dougherty. "This is the fastest-growing server in IBM history," he said.
You're probably saying to yourself, I don't think I really need Linux blade servers. After all, I'm running Unix applications on my servers, and they're doing just fine. Why should I worry about all this?
Well, you can stick with your Unix servers and plod along just fine. But, as Dougherty pointed out, that may not be your best choice. His blades will support Windows, Linux and Unix, so he doesn't have a dog in the OS fight; but he noted, "Customers can build the infrastructure and then deploy the operating environment they need. And they allow you to greatly simplify your IT structure." He also mentions that many of the Unix systems out there now are six or seven years old, and technology does march on, after all.
What kind of savings can you get? How much can you simplify? Dougherty threw out numbers like up to a 40% reduction in total cost of ownership for people moving to blade servers, and as much as an 85% reduction in cabling for blade installations over conventional rack-mount or box servers. That's because of the backplane in the box that houses the blade servers, which handles interconnects between server blades and things like Ethernet switches, routers, fibre channel switches and similar hardware. Incorporating these things into the chassis means that fewer wires have to run, and each of those wires is, of course, a point of failure.
But perhaps the best savings you get is in management. That's what Joe Clabby thinks. "The real thing is blade-management software," said the practice director for Summit Strategies. "You may want to tear down a Unix image and build up some Windows images," for example. With blade servers, and with the blade management software, you can do that easily, Clabby said. He draws this conclusion from his research on IBM and RLX Technologies Inc., the inventor of blade server technology, in The Woodlands, Texas.
"We push these things really hard," Burns said. He's running 504 dual-processor blade servers, which amounts to 1,008 CPUs, in the data center. "I can't imagine a data center with that number of servers in boxes or in racks. It would be impossible to manage on the scale and with the speed that we need. We need to be able to say, 'These six servers should be working on Task A, while these other 84 servers have to be working on another task.' We get these demands from production, and when we do, we have the flexibility to mix and match as required. We can manage 500 blade servers from a single console."
Burns is using xCat to manage his Linux blades. It's a management program that he said IBM donated to the open source movement, and it makes life very easy in this high-stress environment. "Say you're running a blade server and something goes wrong," he explained. "Our procedure is to pull the blade and toss it on a pile, then get a new one from our spares and plug it in. We use xCat to load the image of the server we need, boot up and tell the queue manager that it's ready. We're up and running with a new server in 12 minutes."
That's a far cry from the way you'd handle a down server in any other kind of scenario.
So what are the advantages of Linux blades? Clabby summarized: Cost, space, resource consumption and the ability to build and teardown rapidly. "It's all about a better way to manage your infrastructure," IBM's Dougherty agreed. And Burns added, "Normally, I'd say space, power and heat. But with this number of servers, it's impossible to deal with that with boxes or rack-mount servers."
Linux and blade servers seem to be working for Burns. Maybe the combination would work for you as well.
David Gabel has been testing and writing about computers for more than 25 years.