Microsoft's plan to fill its mammoth Chicago data center with servers housed in 40-foot shipping containers has experts wondering whether the strategy will succeed. In Microsoft's plan, each container in the data center, still being built, will be filled with several thousand servers.

Computerworld queried several outside experts -- including the president of a data center construction firm, a data center engineer-turned-CIO, an operations executive for a data center operator and a "green" data center consultant -- to get their assessments of the strategy. While they were individually impressed with some parts of Microsoft's plan, they also expressed skepticism that the idea will work in the long term.

Here are some of their objections, along with the responses of Mike Manos, Microsoft's senior director of data center services. Manos talked with Computerworld in an interview after the Data Center World show at which Microsoft's plan was announced.

1. Russian-doll-like nesting (servers, on racks, inside shipping containers) may work out to less Lego-style modularity, as some proponents claim, and more mere ... moreness.

Server-filled containers are "nothing more than a bucket of power with a certain amount of CPU capacity," quipped Manos.

His point is that setting up several thousand servers inside a container in some off-site factory setting will make them nearly plug-and-play once the container arrives at the data center. By shifting the setup to the server vendor or system integrator and then wrapping it up inside a 40-foot metal box, containers become far easier and faster to deploy than individual server racks, which have to be moved one at a time.

But people like Peter Baker, vice president for information systems and IT at Emcor Facilities Services, argue that in other ways, containers still "add complexity."

"This is simply building infrastructure on top of infrastructure," he said.

One example, says Baker -- who worked for many years as an electrical engineer building power systems for data centers before shifting over to IT management -- is in the area of power management. Each container, he says, will need to come with some sort of UPS (uninterruptible power supply) that does three things: 1) converts the incoming high-voltage into lower usable DC voltages; 2) cleans up the power to prevent it from spiking and damaging the servers; 3) provides backup power in case of an outage.

The problem is that each UPS, in the process of "conditioning" the power, also creates "harmonics" that bounce back up the supply line and can "crap up power for everyone else," Baker said.

Harmonics is a well-known issue that's been managed in other contexts, so Baker isn't saying the problem is unsolvable. But, he argues, the extra infrastructure needed to alleviate the harmonics generated by 220 UPSs -- the number of containers Microsoft thinks it can fit inside the Chicago data center -- could easily negate the potential ROI from using containers.

Manos' rebuttal: "The harmonics challenges have long been solved [by Microsoft's] very smart electrical and mechanical folks," he said, though he declined to go into specifics. Manos added that he also "challenged the assumption" that Microsoft's solutions are bulky and non-cost-effective: "You can be certain that we have explored ROI and costs on this size of investment." He also admonished critics' speculation that relies too heavily on the "traditional way of thinking about data centers," again, without going into detail.

2. Containers are not as plug-and-play as they seem.

Servers normally get shipped from factory to customer in big cardboard boxes, protected by copious Styrofoam. Setting them up on vibration-prone racks before they travel cross-country by truck is a recipe for broken servers, argues Mark Svenkeson, president of Hypertect Inc., a Roseville, Minn., builder of data centers. At the very least, "verifying the functionality of these systems when they arrive is going to be a huge issue."

But damaged servers haven't been a problem, claimed Manos, since Microsoft began deploying containers at its data centers a year ago.

"Out of tens of deployments, the most servers we've had come DOA is two," he said. Manos also downplayed the labor of testing and verifying each server. "We can know pretty quick if the boxes are up and running with a minimum of people," he said.

He also pointed out that Microsoft plans to make its suppliers liable for any transit-related damage.

So let's say Microsoft really has solved this issue of transporting server-filled containers. But part of what makes the containers so plug-and-play is that they will, more or less, sport a single plug from the container to the "wall" for power, cooling, networking and so forth.

But, Svenkeson pointed out, that also means that an accident such as a kicked cord or severed cable would result in the failure of several thousand servers, not several dozen. It's like those server rooms that go dark because somebody flicks the uncovered emergency "off" switch out of curiosity or spite.

"If you're plugging all of the communications and power into a container at one point, then you've just identified two single points of failure in the system," Svenkeson said.

While Manos conceded the general point, he also argued that a lot "depends on how you architect the infrastructure inside the container."

Outside the container, Microsoft is locating services worldwide -- similar to Google's infrastructure -- in order to make them redundant in case of failure. In other words, users accessing a hosted Microsoft application, including Hotmail, Dynamics CRM or Windows Live, may connect to any of the company's data centers worldwide.

That means that "even if I lose a whole data center, I've still got nine others," Manos said. "So I'll just be at 90% serving capacity, not down hard."

Microsoft is so confident its plan will work that it's installing diesel generators in Chicago to provide enough electricity to back up only some, not all, of its servers.

Few data centers dare to make that choice, said Jeff Biggs, senior vice president of operations and engineering for data center operator Peak 10 Inc., despite the average North American power uptime of 99.98%.

"That works out to be about 17 seconds a day," said Biggs, who oversees 12 data centers in southeastern states. "The problem is that you don't get to pick those 17 seconds."

3. Containers leave you less, not more, agile.

Once containers are up and running, Microsoft's system administrators may never go inside them again, even to do a simple hardware fix. Microsoft's research shows that 20% to 50% of system outages are caused by human error. So rather than attempt to fix malfunctioning servers, it's better to let them die off.

To keep sysadmins from being tempted to tinker with dying servers, Microsoft plans to keep its Chicago IT staff to a total of 35. With multiple shifts, that works out to fewer than 10 techs on-site at any given time. That's despite the 440,000 or more servers Microsoft envisions scattering across the equivalent of 12 acres of floor space.

But where Manos sees lean and mean, others envision potential disaster.

"It seems pretty thin to me," said Svenkeson, who has been building data centers for 20 years. "These are complex systems to operate. To watch them remotely and do a good job of it is not cheap."

As more and more servers go bad inside the container, Microsoft plans to simply ship the entire container back to the supplier for a replacement.

It becomes a problem, then, of defining the tipping point. As more servers die, the opportunity cost of not replacing the container grows bigger and bigger.

"Say 25% of the servers have failed inside a container after a year. You may say you don't need that compute capacity -- fine," said Dave Ohara, a data center consultant and blogger. "But what's potentially expensive is that 25% of the power committed to that container is doing nothing. Ideally, you want to use that power for something else.

"Electrical power is my scarce resource, not processing power," Ohara concluded.

Biggs agreed.

"Intel is trying to get more and more power efficient with their chips," Biggs said. "And we'll be switching to solid-state drives for servers in a couple of years. That's going to change the power paradigm altogether."

But replacing a container after a year or two when a fraction of the servers are actually broken "doesn't seem to be a real green approach, when diesel costs $3.70 a gallon," Svenkeson said.

Manos acknowledged that power is somewhat "hard-wired" within the data center, making it difficult to redistribute. But he asserted that if a data center is "architected smartly on the backside, you can get around on those challenges, by optimizing your power components and your overall design." He declined to elaborate.

If containers need to be swapped out before expectation, that cost will be borne by the container vendor, not Microsoft, said Manos.

But he hinted that Microsoft is willing to tolerate a fairly large opportunity cost -- that is, hold onto containers even if a large percentage of the servers have failed and are taking up valuable power and real estate as a result. "I don't know too many people who are depreciating server gear over 18 months. Rather, I see pressure to move out to a five-to-six-year cycle."

4. Containers are a temporary, not long-term, solution.

To meet its late summer opening date for the Chicago data center, Microsoft has already opened the containers up for bid. Manos declined to comment on which vendors are in the running, but he confirmed that Microsoft hopes to award contracts to multiple vendors.

Microsoft is in the midst of its huge data center expansion in order to accommodate its growing Windows Live and Office Live online services. As a result, containers provide an "excellent opportunity to increase the scale unit, from server, to rack, to server to mini data center," Manos said.

But what happens when expansion inevitably slows? Eventually, adding servers one 2,000-server container at a time will start to feel like going to Costco to buy a 50-pound bag of dog food for your toy poodle.

"I think this is a very short-lived, ephemeral model that may work right now," said Biggs, who added that most data centers operators, such as Peak10, have no interest in containers because the scale is simply too large for them and their customers.

"The only thing interesting to me about containers is the predictability of how much power you need and how much heat you'll produce," he said. "Otherwise, they're kind of a novelty."

That's why some observers, such as Ohara, say the market is actually in smaller units. A former supply chain engineer for both Hewlett-Packard and Apple, Ohara has been developing his own prototypes for a "server cube" that would weigh about 1,000 pounds and measure 1 meter in each dimension -- hence the name of his blog, GreenM3.

"It's taking what's in a server rack but putting it into a cube to make it more efficient to roll out," he said. "That potentially could apply to many more people."

Manos agreed that containers aren't the be-all and end-all for data centers, including Microsoft's. He pointed out that the second floor of the Chicago data center will still be fully comprised of conventional free-standing server racks.

"For us, it is about right-sizing the scale with the 'needs and speeds' of deployments," he said. "As it stands today, containers deliver on this goal."

"If trends continue as anticipated, containers will continue to be an important piece to the puzzle, but not the only piece," he said. But Manos also acknowledged, "The only true constant in technology is that technology will change. Whether that means the server compute form factor changes I can only guess."

5. Containers don't make a data center greener.

Microsoft has not-so-subtly tried to portray its new data centers as being exemplars of green computing. In San Antonio, the site of an upcoming 470,000-square-foot data center, construction workers built around an old live oak tree on the 44-acre site, even putting up concrete barriers to help protect it according to the local newspaper. It also plans to use recycled gray water in the data center and install the most efficient hardware, power and cooling systems.

Apart from preserving old-growth oak trees, Microsoft is doing many of the same things at its Chicago data center. Another thing about locating in the Windy City is that it is considered the most energy-efficient U.S. city in which to locate a data center.

Indeed, Microsoft said late last year that being in Chicago will enable it to use "all sorts of cold-air cooling options in the winter months," a process known as airside economization.

An airside economizer, explained Svenkeson, is a fancy term for "cutting a hole in the wall and putting in a big fan to suck in the cold air." Ninety percent more efficient than air conditioning, airside economizers sound like a miracle of Mother Nature, right?

Except that they aren't. For one, they don't work -- or work well, anyway -- during the winter, when air temperature is below freezing. Letting that cold, dry air simply blow in would immediately lead to a huge buildup of static electricity, which is lethal to servers, Svenkeson said.

To keep the humidity at the 30% minimum of most data centers, water would need to be added to the air as it blows in. But that requires exorbitant amounts of energy and can create a huge condensation problem if done wrong.

"You'll quickly have an ice-side economizer," Svenkeson quipped.

Airside economizers actually work better in warmer climates, or in places such as the American Southwest where temperatures drop quickly (but not below zero) at night, Svenkeson said. Or they can work in office environments, where maintaining a minimum humidity is easier because of the workers inside and also less vital.

A less risky solution is using an air conditioning system that can be transformed during the winter into a so-called closed-loop liquid cooling system . This process essentially involved exposing coolant-bearing pipes to the hot air inside the data center. The coolant absorbs the heat and expands, rushing through the pipes to the outside of the building. There, it cools, shrinks and flows back inside, where it repeats the process.

While closed-loop systems are "wickedly efficient," according to Biggs, they still take a lot of energy to work. "There's no free lunch. The laws of physics haven't been repealed."

Even with cutting-edge cooling systems, it still takes a watt of electricity to a cool a server for every watt spent to power it, estimated Svenkeson.

"It's quite astonishing the amount of energy you need," Svenkeson said.

Or as Emcor's Baker put it, "With every 19-inch rack, you're running something like 40,000 watts. How hot is that? Go and turn your oven on."

Manos acknowledged that Microsoft's initial plan to use only air-side economizers, especially during the winter, was overly optimistic. As a result, the Chicago data center will use both air and liquid cooling. "We're optimizing for both extremes," he said.

Manos wouldn't go into details, except to say "an entire organization of research and engineering people" is working on cooling and power issues. "I'm not sure if we're doing anything more revolutionary in this space, but a lot of the problems have been solved."

And he emphasized that with the cost of power making up the vast majority of the ongoing cost of its data center operations, Microsoft has every incentive to make sure they are as energy-efficient as possible.

But with Microsoft building three electrical substations on-site generating a total of 198 megawatts, or enough to power almost 200,000 homes, green becomes a relative term, others say.

"People talk about making data centers green. There's nothing green about them. They drink electricity and belch heat," Biggs said. "Doing this in pods is not going to turn this into a miracle."

6. Containers are a programmer's approach to a mechanical engineer's problem.

Some say that there are good reasons why geeks have given Microsoft a free pass so far on its containers plan. First, they seem to offer a long-overdue paradigm shift in power and cooling problems that, by comparison, seem to routinely occur in software and other areas of IT, but that haven't yet really happened for power and cooling.

"I think IT guys look at how much faster we can move data and think this can also happen in the real world of electromechanics," Baker said.

Another is that techies, unfamiliar with and perhaps even a little afraid of electricity and cooling issues, want something that will make those factors easier to control, or if possible a nonproblem. Containers seem to offer that.

"These guys understand computing, of course, as well as communications," Svenkeson said. "But they just don't seem to be able to maintain a staff that is competent in electrical and mechanical infrastructure. They don't know how that stuff works."

Svenkeson tells the story of the data center manager whose UPS systems kept overloading, even though he had each of them set at only 80% load. Turns out, the pair of UPSs was running 160% of the maximum load through his servers, which is why they kept failing.

Attempting to eliminate these variables through plug-and-play containers "is a fairly natural response," Svenkeson said, though he believes it's the wrong one. He argues that containers will ultimately be seen as a "fast-food approach."

"It might be a viable market, but only for a limited time," he said. "As soon as the first containers arrive with a bunch of broken processors inside, that will be the end of it."

Manos is unfazed. Much of the criticism, he implied, is knee-jerk.

"Data centers are very conservative," he said. "You go into one built a year ago or one built 10 years ago and they'll look very similar."

Microsoft had been testing containers for almost a year before it started talking about them publicly, Manos said. What Microsoft has revealed so far is just the tip of the iceberg. When critics learn more, he says, they'll be convinced.

"Half of the people say this is the greatest thing they'd ever heard. The other half say this will never work inside a data center," Manos said. "But the fact of the matter is that this does work."