[superuser2]

I found the reports about the outage - it was 2007 (so obviously much more than a year ago) but very similar to one of Amazon's recent outages - the truck took out a transformer, Rackspace fired up backup power, but cooling failed to start so Rackspace had to shut it all down to avoid melting everything.

Looks like Amazon wasn't the only one with inadequate testing of their continuity plan. And I don't think Rackspace offered alternate Availability Zones at that point.