What is S3 storage?

What it is

Amazon S3, short for Simple Storage Service, is the object storage service inside Amazon Web Services. A program hands it a file and a name, and S3 keeps the file in a container called a bucket. There are no drive letters or folders in the usual sense. Each object has a key, and programs read and write objects through an API using an access key and a secret.

Other systems copied that API. Ceph, MinIO, and most cloud providers offer storage that answers the same requests, so software written for Amazon S3 can usually be pointed at a different address and keep working. That is what S3-compatible means, though less common features such as object lock are not supported everywhere.

Why it matters to a business

• Backups have a standard target: most backup tools can write to an S3 bucket, so the choice of tool and the choice of storage are separate decisions.
• You choose where the data lives: the same backup job can write to Amazon, to another provider, or to S3-compatible storage run by a company you know.
• Versioning and locking: a bucket can keep earlier versions of an object, and object lock can stop a copy from being changed or deleted for a set time, which helps against ransomware.
• Keys are the risk: anyone holding the access key and secret can read or delete what that key allows. A bucket set to public by mistake is a common way data leaks.

How KawaConnect works with S3

We host our own encrypted S3-compatible object storage on Ceph, and use it for offsite backup copies. Each client gets separate buckets and its own credentials. Because the storage speaks the standard S3 interface, the backup tools a business already uses can usually write to it without changes. When a client prefers Amazon S3 or another provider for the offsite copy, we set that up instead and manage the keys.

Learn more

• Amazon S3 on WikipediaA neutral overview of the service, its history, and how buckets and objects work.
• Amazon S3 product pageAmazon's own description of the service and its storage classes.
• Amazon S3 user guideThe official manual, covering buckets, access control, versioning, and object lock.
• Ceph Object Gateway documentationHow Ceph provides S3-compatible storage, for readers who want the technical detail.