Question

We store some sensitive stuff on S3 and on our instance filesystems on AWS. Is there a way to securely wipe it?

Answer 1

The short answer is no, there is no wipe utility. If you delete the file permanently, the file is gone and it cannot be recovered (unless you have snapshots or other items that might keep the file stored). However, there is not a way to wipe the disk. Don’t forget, though, that AWS uses server virtualization so that your disk storage does not necessarily correspond to one physical disk platter. Instead, it is a virtual storage system spread over many drives. When your file is deleted, it is gone from public access. Then Amazon designates that area of disk for write-only operations so that your data gets overwritten quickly.

Here is a quote from an Amazon document about their data security:

When an object is deleted from Amazon S3, removal of the mapping from the public name to the object starts immediately, and is generally processed across the distributed system within several seconds. Once the mapping is removed, there is no external access to the deleted object. That storage area is then made available only for write operations and the data is overwritten by newly stored data.

Retrieved from: http://aws.amazon.com/whitepapers/overview-of-security-processes/