Amazon Web Services has launched a public beta test of AWS Storage Gateway, which allows enterprises to back up application data in Amazon's cloud using a software appliance, the company said on Tuesday.
The Storage Gateway appliance is a virtual machine that runs on VMware's virtualisation software. It uses an iSCSI interface to integrate with applications.
The appliance stores data on local storage hardware, while uploading backup snapshots to Amazon's cloud. This provides low-latency access to data and off-site backups in the cloud, Amazon wrote in a blog post.
There is no limit to the amount of storage that a single gateway can upload to Amazon's S3 (Simple Storage Service). But each gateway can handle up to 12 TB of local storage and up to 12 storage volumes. Those that need more local capacity can ask Amazon for special permission, according to a FAQ that details the service.
Amazon also plans to add what it calls gateway-cached volumes in the coming months.
Data written to those volumes will be stored using S3, with only a cache of recently written and frequently accessed data stored on the local hardware. Gateway-cached volumes will allow enterprises to use Amazon's cloud for data where higher latencies are acceptable, it said.
At present, the appliance is only configurable via the AWS Management Console.
Enterprises that want to use Storage Gateway pay a monthly fee of $125 (£80) per activated gateway. Added to that is the cost of storage capacity used by the snapshots, and traffic out of Amazon's cloud.
The snapshots are stored and billed as Amazon EBS (Elastic Block Store) snapshots, which cost from $0.14 per GB per month.
The cost of data transfer drops as the amount of data increases: Up to 10 TB of transferred data in one month costs $0.12 per GB, and the next 40 TB costs $0.09 per GB. Rate tiers are chosen based on aggregate usage across multiple Amazon services, including EC2 (Elastic Compute Cloud), S3 and VPC (Virtual Private Cloud).
There is also a free usage tier that allows enterprises to test the service for a limited time without being charged.