Amazon has finally restored the “great majority” of its EC2 customers after a failure on its Elastic Block Storage (EBS) cloud DBMS left websites in limbo. The outage has already generated more than its share of commentary, and as usual there are more extreme views than useful ones. Some say that the problem demonstrates that the cloud isn’t reliable, some that it demonstrates that the cloud is perfect. It demonstrates both, neither, in my view.
What the Amazon problem shows is first that our view of the cloud is simplistic to the point of being dangerous, but that’s true about the popular view of just about everything these days, it seems. Second, it shows that people aren’t looking deeply enough into cloud computing when they commit to it. There’s no substitute for knowing what you’re doing. But third, providing any form of high reliability is always harder when you’ve ceded control to a third party. Nobody at the enterprise level has any good feel for how EBS might impact reliability; they don’t have it. Given that, all you can do is to rely on an SLA, and anyone who’s ever looked at a cloud SLA knows that in the end it’s not particularly valuable.
Technology isn’t the only place where we’ve got unresolved problems. The flap over S&P’s threat to downgrade US debt has pushed the political debate into high gear, which radically lowers the chances of any responsible action. The US economy slipped in Q1; we’ll know how far later this week, but it’s not likely to have grown much more than 1.5%. Part of that is high oil prices, part the highly politicized debate over the US deficit and the conviction of voters that nobody will do anything useful. Wake up, Washington.
