Versioning

If you enable versioning for a bucket, POST automatically generates a unique version ID for the object being added. Amazon S3 returns this ID in the response by using the x-amz-version-id response header.

If you suspend versioning for a bucket, Amazon S3 always uses null as the version ID of the object stored in a bucket.

For more information about returning the versioning state of a bucket, see GET Bucket (Versioning Status).

Amazon S3 is a distributed system. If you enable versioning for a bucket and Amazon S3 receives multiple write requests for the same object simultaneously, all versions of the object are stored.

To see sample requests that use versioning, see Sample Request.