This is something I’ve been thinking about quite a bit lately, and in fact just a few days ago I was happy to learn that our paper, Disaster Recovery as a Cloud Service: Economic Benefits & Deployment Challenges, has been accepted into this year’s Workshop on Hot Topics in Cloud Computing (HotCloud 2010).  In our paper, we survey why we think cloud computing platforms are going to become increasingly popular for providing cheap disaster recovery services.

Clouds can be used to provide a variety of backup mechanisms ranging from cold replicas that are periodically synchronized up to hot standbys that are always in sync and can take over as soon as a failure is detected.  In practice, we think that a middle class of warm replicas is where the cloud can provide the greatest benefit.  A warm replica could be implemented as an EC2 VM that is not aways running, but whose disk (an EBS volume) is kept regularly up to date by a replication manager VM.  This replication manager can handle synchronizing the disk state for a large number of applications, but the customer will not have to pay for the active VM costs of those applications until a failure actually occurs and the VMs are booted up.

Check the paper for all the details, including a cost analysis of providing DR for various application types.