Rackspace offers both traditional hosting of dedicated servers, and a cloud service that offers access to virtualized server instances. In general, cloud customers were not affected by the power outages, Napier said. But the Rackspace cloud system suffered problems of its own this week, with “intermittent times” and error messages. Napier said the Rackspace cloud suffered from a network problem, rather than a power failure.

All in all, the incidents this week were not as bad as another affecting the same Dallas facility in November 2007, Napier said. In that case, a truck missed a turn and took out a transformer, ultimately taking the entire facility offline, he said.

“Both [incidents] were very painful and very disappointing,” he said.

Although the most recent troubles affected just a portion of one out of Rackspace's nine data centers, Napier noted that “for each customer that's impacted, it's everything to them. Our job is not to have this happen.”

Rackspace made use of Twitter in the wake of its most recent outages, updating customers and letting customers report issues over the social networking site. But that's just one outlet for communicating with users, he says.