On-premises data centres are expensive to build and operate, which is one reason public cloud is so attractive … albeit not so attractive that organisations will immediately evacuate on-premises data centres.
But it is generally accepted that lots of workloads will migrate to the cloud in coming years and that hybrid clouds will become very common. And that migration means data centres built for pre-cloud requirements are unlikely to be full in future.
Which raises the question of what to do with empty space in a perfectly good data centre full of expensive electrical and cooling kit.
The Register's asked around and deduced you have a few options.
One is doing literally nothing other than unplugging kit that's no longer in use. This isn't a mad idea because your on-premises data centre was designed to cool certain kit in certain places. Leaving decommissioned devices in place won't disrupt those cooling concoctions. It can also save you the cost of securely destroying devices, because you'll know exactly where your decommissioned kit can be found and if you've built your data centre right you'll know it's well-secured.
Another idea advanced by Tom Anderson, Vertiv's* ANZ data centre infrastructure manager, is to optimise the room for its new configuration. This can be done by placing temporary barriers on newly-empty racks so that cold air doesn't waft into empty space. Doing so creates a smaller volume that needs less cooling. He also recommends throttling back cooling and UPSes because they'll be more efficient under lighter workloads. Those running dual cooling units, he suggests, could run one at a time and switch between units.
An old data centre can also be useful as a disaster recovery (DR) site. Plenty of organisations outsource a DR site. Newly-freed space in one facility gives you one of your own.
The world has an insatiable appetite for data centres, so renting out your spare space is another option. But a Gartner study titled “Renting Your Excess Data Center Capacity Delivers More Risk Than Reward” may deter you from exploring it. Analyst Bob Gill warns that most organisations just aren't ready to become a hosting provider, because it's a specialist business. It's also a business in which clients have very high expectations that would-be-hosts have to learn in a hurry. He also worries about reputational risk flowing from news of a security breach.
The study also notes that becoming a service provider means signing away data centre space for years, depriving you of an asset you could conceivably covet before contractual obligations expire.
Gill doesn't rule out the idea, but says “the complexities and risks of offering commercial colocation will confine the majority of such offerings to educational and governmental agencies and vertical industry ecosystems”.
Creative - gulp! - re-use strategies
At this point of the story many of you may also be wondering if a partly-empty bit barn is a useful place to store booze. Sadly it's not a good idea: wine is best stored at between 7C and 18C, but modern data centres run in the low twenties. Beer won't be much fun at that temperature. Data centres also tend to be rather lighter than a good wine cellar.
Bit barns are also be a poor place to store documents, because they tend to run a little wetter than the United States Library of Congress' recommended 35 per cent relative humidity. Paper also prefers to be away from air currents and data centres are full of them.
But a partly-empty data centre is a good place to store … computers. Which may seem stupidly obvious until you consider that some workloads just aren't a good fit for the cloud. Vertiv's Anderson suggested that video surveillance footage is so voluminous that moving it to the cloud is costly and slow, but that some spare racks could happily let you consolidate video storage from around your organisation into one place.
Emerging workloads like AI and big data can also demand very hot and power-hungry servers. A dense, full, data centre may have struggled to house that kind of application. A data centre with some empty racks may be able to accommodate those workloads. That such applications tend to use large data sets and have high compute-affinity – they work best when storage and servers are physically close – makes them strong candidates for on-premises operations.
A final option is just to knock over the walls of a data centre, lay down some new carpet and use the space for whatever purpose you fancy.
If you've found a good use for un-used data centre space, feel free to let me know or hit the comments. ®
Bootnote: A final treat, brought to El Reg's attention by a chap named John White: an IBM faux cop show from the golden age of server consolidation, of a standard to rank with vendors' dire rock video pastiches. Enjoy. If you can.
* Vertiv used to be Emerson Network Power