The trend towards using external air to cool data centres comes with the problem of what happens if it gets too hot outside. You don’t want the once-every-twenty-years heat wave to bring your data centre to its knees. It’s something that server manufacturers have been working on.
Dell carried out a series of tests to see whether its PowerEdge servers could withstand higher temperatures without impacting performance. The net result is that ‘fresh air’ specifications were built into every platform of the latest generation of the servers, launched in February. Customers can choose to raise the temperature in a data centre to take advantage of the operational savings or can even build their next data centre completely without chillers.
Dell analysed climate data from the US, Europe and Asia and found that, to enable the widespread deployment of minimal cooling requirements in data centres, IT equipment should be able to withstand short term temperature peaks of up to 45C/113F. So Dell’s new servers can tolerate 900 hours of 104°F (40°C) operation per year and up to 90 hours at 113°F (45°C). Most commercially available IT equipment is rated at a maximum temperature of only 35C.
It does raise complications - network equipment such as switches often share a data centre rack with servers and storage, but no equipment can run at higher temperatures unless everything can. So Dell also offers fresh air capable storage, networking and power products to make sure nothing is holding back the hotter-running facility.
Dell has talked about this range of hotter running servers for a while and no doubt other manufacturers will follow. It should open the way for at least wider adoption of free-air cooled data centres.
In fact it’s been generally accepted for some time that most IT equipment can run hotter than the manufacturers’ specifications without problems, but data centre managers are understandably reluctant to take responsibility should anything go wrong. The supplier needs to guarantee that the equipment will withstand the temperature and provide standard support if there are any problems.
Even for these new Dell servers there is a limit on the time that the equipment can run hot. It means data centre managers will need to closely monitor temperature levels to ensure these manufacturer maximums are not exceeded and vendor support lost. I suspect that some (if not many) will stick with lower temperatures as a result.