What might the outer limit for modular data centers look like? It could resemble the micro data center prototype unveiled this week by AOL. The rack-sized enclosure, which will live outdoors, is the first step in AOL's ambitious plan to reshape its infrastructure using small, unmanned IT facilities that can be managed remotely.
The new strategy builds upon AOL's work in deploying an "lights out" data center last year, according to Michael Manos, the CTO of AOL Services, who disclosed the micro data center design in a blog post. Manos said the high-density enclosure, which can house thousands of virtual machines, was deployed Wednesday at an AOL facility in Dulles, Virginia. Manos envisions a distributed network of micro data centers, allowing AOL to quickly roll out new IT capacity and create its own content distribution network (CDN).
"Out on a lonely slab of concrete in the back of one of the buildings our future has taken shape," Manos wrote. "The inherent flexibility of the design allows us a greater number of places around the planet where we can deploy capacity, and that is pretty revolutionary. We are no longer tied to traditional data center facilities or colocation markets. That doesn’t mean we won't use them; it means we now have a choice."
Easy Deployment in Any Geography
The AOL Micro Data Center can run high-density server deployments in virtually any climate, and doesn't require the industrial-strength infrastructure typical of most data centers, according to Manos. "The power requirement for each box is easily sustained at any office building around the world," he said.
AOL's approach is a new take on a concept that has been on the market for a number of years. Companies like Elliptical Mobile Solutions, SGI (Rackable) and AST Modular were offering micro enclosures as early as 2008. These rack-sized units have been marketed for remote offices, mobile deployments and temporary IT capacity for the military or disaster relief. But they've been a niche product, as companies historically have been wary of deploying IT gear outdoors in small enclosures, preferring an indoor IT closet.
That attitude began to change as the industry challenged the assumption that server reliability would suffer at warmer temperatures. This realization prompted wider adoption of free cooling - the use of fresh air to cool servers and reduce data centers' reliance on power- hungry chillers and air conditioners. A number of companies, including Microsoft, incorporated free cooling into containerized data center designs that could live outdoors.
Modular Gets Smaller
Manos, who was previously the GM of Microsoft's data center operations, has applied those lessons to his vision for AOL's infrastructure of the future. "Having been an early adopter of container based solutions at Microsoft, I know a lot of the pitfalls, and this smaller form factor fixes many of those," said Manos.
The AOL Micro Data Center will feature a rack-size enclosure filled with servers and networking equipment, with hookups for power, networking and water. The unit will use use air-side economization (introducing outside air into servers to keep them cool) but will also include a direct expansion (DX) cooling systems, in which air passes over the cooling coil of an air conditioning unit. This configuration provides a combination of efficiency and reliability, allowing the system to use fresh air cooling as the default and switch to DX cooling if the weather gets too warm.
The micro data center can live on a slab outdoors. Manos said most units would be deployed in a fenced area monitored by security cameras.
"Security is always a concern, but in general these devices have more in common with equipment you would see in an equipment yard for most buildings than standard data center environments," he said. "Wide-scale deployed units won't have the fancy paint jobs and logos, so they will very much look at home in those equipment yards. Given the nature of our technology set, should a catastrophic event or malicious damage occur, we have the abilities to swing the IT load around to other nearby instantiations."
Form Factor for Hyperlocal Sites?
AOL's new approach to infrastructure is driven by the company's focus on content. As the company builds its portfolio of blogs and web sites – which includes The Huffington Post as well as blogs like Engadget and the Patch network of hyperlocal news sites – it is adopting a flexible infrastructure that can deploy server capacity quickly in locations with strong user populations.
With its first unmanned data center, AOL demonstrated the ability to deploy remotely-managed IT equipment in chunks of 500 kilowatts to 1 megawatt of server capacity. With the micro data enter, it is further shrinking its footprint and its budget.
"It can all be done in a very low cost envelope, compared to traditional build and operating costs," said Manos. "This gives us incredible flexibility on either entering new markets or driving more hyperlocal to our consumers. This is incredibly important for all of our products but particularly useful for platforms like Huffington Post and Patch, where these are key drivers and cost is an issue."
The small, standardized form factor of the AOL Micro Data Center allows it to be deployed quickly in multiple locations. This could also enable AOL to assemble an "edge network" of distributed nodes that move its content closer to end users, which would reduce the company's reliance on commercial content delivery networks like Akamai and Limelight. "Remember that we still have a Tier 1 ISP designation, and the ability to go local could allow us to do some very interesting edge compute services or just reduce operational costs on existing spend," said Manos.
Micro data centers have also figured in some interesting research on incorporating renewable energy into data center operations. Rutgers University and HP have coupled small data centers with photovoltaic arrays, allowing servers to run on solar power. This creates the potential for networks of micro data centers, each supported by solar power, that can operate together to enable a "follow the sun" strategy in which IT workloads shift across regions throughout the day.