Ceph
Unified, software-defined distributed storage providing block, object, and file storage at exabyte scale — the industry standard for OpenStack and Kubernetes.
Overview
Ceph is a unified distributed storage system that provides block (RBD), object (RGW/S3), and file (CephFS) storage from a single cluster. It uses the CRUSH algorithm for deterministic data placement, eliminating central lookup tables. Ceph is the default storage backend for OpenStack and widely used with Kubernetes (via Rook).
Key Facts
| Attribute |
Detail |
| Repository |
github.com/ceph/ceph |
| Stars |
~14k+ ⭐ |
| Latest Version |
v20.2.1 "Tentacle" (April 6, 2026) |
| Language |
C++, Python |
| License |
LGPL 2.1 / 3.0 |
| Governance |
Community + Red Hat / IBM |
Evaluation
| Pros |
Cons |
| Unified: block + object + file |
Complex to deploy and operate |
| CRUSH: no SPOF, linear scaling |
High resource requirements (RAM, CPU) |
| Self-healing, auto-rebalancing |
Tuning required for optimal performance |
| Industry standard (OpenStack, K8s) |
Erasure coding historically slower (improved in Tentacle) |
| Exabyte-scale proven |
OSD recovery can saturate network |
| Cephadm for lifecycle management |
|
| FastEC in v20: better EC performance |
|
Key Features (Tentacle v20.2)
| Feature |
Detail |
| FastEC |
Major erasure coding performance improvement for small I/O |
| SMB Manager |
Integrated Samba/CephFS SMB shares with AD support |
| SeaStore preview |
Next-gen OSD object store for NVMe devices |
| Multi-cluster dashboard |
Manage multiple Ceph clusters from one UI |
| OAuth 2.0 |
Dashboard authentication |
| NVMe/TCP gateways |
NVMe-oF target support |
| RBD transient locks |
Better exclusive lock handling |
Storage Interfaces
| Interface |
Protocol |
Use Case |
| RBD |
Block (RADOS Block Device) |
VM disks, K8s PVs, databases |
| RGW |
Object (S3/Swift API) |
Backups, media, data lakes |
| CephFS |
File (POSIX) |
Shared filesystems, NFS replacement |
Sources