Ceph is an Open Source Distributed storage solution and it puts together to simplify the highly scalable object, file-based storage and block under one whole system.

Ceph supports both scale-up and scale-out using economical commodity hardware. Clusters of Ceph are constructed with the help of an algorithm called CRUSH (Controlled Replication Under Scalable Hashing) in order to run commodity hardware.

Architecture

Ceph is based on RADOS (Reliable Autonomic Distributed Object Store) and it provides multiple storage interfaces in a single unified storage cluster.

Why Ceph?

Ceph becomes more popular for multiple reasons.

1. Open source: As Ceph is an open-source software there are no licensing fees involved for using Ceph.
2. Ceph storage is software-defined and hence there is no need to depend on expensive hardware. Using Ceph, commodity hardware can be used to build a storage product that is just as scalable and flexible as same as any SAN storage system.
3. Scalability: If you want more capacity there’s no need to purchase additional licenses for Ceph, you can just add more servers.
4. The exclusive aspect of Ceph is that it grants multiple interfaces to access the storage.

Also, Ceph storage offers common features found in any enterprise-grade storage product like snapshots, replication, thin provisioning, and self-healing.

Specific Use Cases

• Large bulk block storage

As Ceph has the ability to design and build cost-effective OSD nodes, Ceph helps us to build large high-performance storage clusters that are very cost-effective compared to all other available storage options.

• Object storage with custom application

We can connect to the in-house application to directly talk to the underlying Ceph RADOS layer using librados. This feature will simplify the development of your application and grant you direct access to highly performant reliable storage.

• Distributed filesystem – web farm

A farm of web servers all need to access the same files so that they can all serve the same content regardless of which one the client connects to.

Commonly, a high-availability NFS solution would be used to provide distributed file access but it has limitations at scale. CephFS can implement a distributed filesystem to store the web content and allow it to be mounted across all the web servers in the farm.