Servers overheated in the warm weather at a London data centre operated by hosting provider Level 3 on Sunday, causing a popular music website to be disrupted for four hours.

According to Level 3, one chiller unit malfunctioned causing the ambient temperature to rise. As temperatures outside reached 22˚C, five more chillers subsequently failed and the temperature inside the data centre rose to 50˚C. This in turn caused servers to malfunction.

A chart of the rising temperature within the data centre can be seen here.

Level 3 customer Last.fm, a popular music recommendation site, kept its customers up to date while its website was unavailable using the Twitter micro-blogging service. Its reactions to the outage can still be read here.