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 C.O.R.E.
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.
