Object storage, as the name suggests, manages data in the form of objects. Each object stores data, metadata, and a unique identifier. Object storage cannot be directly accessed by operating systems as a local or remote filesystem. It can only be accessed via API at application level. Ceph provides an object storage interface known as the RADOS gateway, which has been built on top of the Ceph RADOS layer. The RADOS gateway provides applications with RESTful S3- or Swift-compatible API interfaces to store data in the form of objects into a Ceph cluster.

In a production environment, if you have a huge workload for Ceph object storage, you should configure the RADOS gateway on a physical dedicated machine, else you can consider using any of the monitor nodes as the RADOS gateway. We will now perform a basic RADOS gateway configuration to use Ceph storage cluster as object storage.