I did read about this a while back when the challenges using EC2 was how not lose a database in case of a machine failure. Luckily it never happened and forgot all about EBS, the persistent disk for Amazon EC2. We went live with a new customer over the weekend and EBS came up all over again for data backup. Quite simple to use it.
1. Created a new volume using ElasticFox and attached it to a running instance.
2. Formatted it to ext3 - yes | mkfs -t ext3 /dev/sdh
3. Created a new folder /permnt
4. Mounted it - mount /dev/sdh /permnt
5. That's all, it is up and running.
Its quite a pleasant experience using Amazon's various services - they are so simple to use which always inspires us startups to emulate that simplicity.
Still to check auto backup to S3 from EBS - I am sure it will be as simple.