Microsoft lowered a sealed cylindrical data center that contained 864 servers into the North Sea off Scotland’s Orkney Islands in 2018 | Wikimedia Commons
Microsoft lowered a sealed cylindrical data center that contained 864 servers into the North Sea off Scotland’s Orkney Islands in 2018. The 40-foot-long vessel was placed about 117 feet below the surface as part of Project Natick, which was an experiment designed to test whether data centers could operate reliably on the seabed while using seawater as part of the cooling system. When Microsoft retrieved the vessel in 2020, the company found that the servers inside had experienced a failure rate one-eighth that of its land-based comparison group. Microsoft lowered a sealed cylindrical data center that contained 864 servers into the North Sea off Scotland’s Orkney Islands in 2018 | Wikimedia Commons The Northern Isles module contained 12 server racks that held 864 servers. InformationWeek reported that the cylindrical vessel was approximately 40 feet long and 10 feet wide and was installed at a depth of 117 feet. Microsoft retrieved the Northern Isles module in July 2020 and compared the performance of its servers with a group of land-based machines.
The sealed vessel was filled with nitrogen rather than ordinary air, which created an environment with less oxygen and therefore less potential for corrosion inside the enclosure.
The underwater servers had a failure rate one-eighth that of the land-based control group, to which Microsoft said the result suggested that the controlled environment inside the vessel had produced more reliable operation than conventional conditions. Microsoft’s Project Natick research page says the company believed those factors were responsible for much of the reliability difference, although it also described the explanation as a hypothesis requiring further analysis. Microsoft’s own Project Natick results describe the reliability difference as one of the main findings from the experiment. Microsoft’s researchers proposed two main explanations for the difference, firstly, the nitrogen atmosphere inside the vessel was less corrosive than an oxygen-rich atmosphere, and secondly, the absence of people working around the equipment eliminated some of the physical disturbance that servers experience in conventional data centers.
The project therefore tested whether a sealed data center could operate for long periods without the normal human access associated with land-based facilities. The experiment also used ordinary commercial server hardware rather than equipment created specifically for an underwater installation.
