Amazon Web services to get persistent storage

By Tim Conneally | Published August 21, 2008, 12:16 PM

The Elastic Block Store (EBS), Amazon's block-level persistent storage service for its Elastic Compute Cloud (EC2) has come out of beta, offering more security for databases in the event of instance failures.

For companies relying on cloud-based services, the threat of outages looms large. In July, when Amazon's Simple Storage Service went down for eight hours, dozens of popular sites such as Twitter and SmugMug were disrupted.

EC2 services could formerly only store data tied to an instance locally. If that instance went down, so too did the related data.

With EBS, data can be stored independently and redundantly so that if one piece of hardware goes unavailable in a service, data will not necessarily be lost. Amazon says that EBS volume data is "replicated across multiple servers in an Availability Zone," and estimates the annual fail rate to be between 0.1% - 0.5% for volumes 20 GB and under.

Amazon is offering volumes from 1 GB up to 1 TB which appear mounted just like any other storage device and can be used similarly. Volume storage costs the user 10¢ per allocated GB per month, and 10¢ per 1 million I/O requests.