Ceph

Ceph is open-source distributed storage software that brings object, block, and file storage together in a system organizations run on hardware they choose and manage. Its RGW object storage works with the S3 API and Swift-compatible applications, and offers versioning, lifecycle rules, immutability, and cross-region replication. RBD provides thin-provisioned disk images with snapshots, writable clones, and asynchronous mirroring to remote Ceph clusters. CephFS is a POSIX-compliant distributed filesystem with snapshots, quotas, and multi-cluster mirroring. Ceph can replicate data across devices, racks, and geographic locations, then redistribute it after hardware or connectivity failures. For Kubernetes, the project recommends Rook, and the Ceph CSI driver can provision block and file volumes. Deployment options include cephadm or Kubernetes with Rook. Production guidance calls for at least three monitors, two managers, and three OSDs, with 10 Gb/s networking between hosts. Ceph is free; the listed plan is free. It is available for Linux, Windows, API, and self-hosted environments.

Ceph combines several storage types with replication and recovery capabilities in a system organizations operate themselves. Its deployment and production hardware guidance are important considerations for teams evaluating it.

Ceph suits organizations that want to operate distributed storage on hardware they manage, including businesses, cloud providers, universities, and research institutions. It may also fit teams deploying storage with Kubernetes.

Overview

Ceph is free, open-source software for running object, block, and file storage on hardware an organization chooses and operates. It suits infrastructure teams that need multiple storage types in one distributed system and can take responsibility for the cluster; it is not a managed-storage shortcut.

Founded in 2006, Ceph is stewarded by the Ceph Foundation under the Linux Foundation. Most of the software is dual-licensed under LGPL 2.1 or 3.0, with some bundled components under other free software licenses.

Key features

Ceph's breadth is its central advantage: teams can serve different storage workloads from a common system instead of adopting a separate product for each. That consolidation comes with the work of selecting, deploying, and maintaining the hardware and cluster.

• Object storage: RGW supports the S3 API and Swift-compatible applications. Versioning, lifecycle rules, immutability, and cross-region replication make it a capable fit for teams whose applications need established object-storage interfaces and controls.
• Block storage: RBD provides thin-provisioned disk images, snapshots, writable clones, and asynchronous mirroring to remote Ceph clusters. Its integrations include Kubernetes, QEMU, libvirt, OpenStack, Nomad, and CloudStack, useful for varied infrastructure. Block storage requires a running Ceph cluster, so RBD is not a standalone option.
• File storage: CephFS is a POSIX-compliant distributed filesystem with snapshots, quotas, and multi-cluster mirroring. Metadata servers can scale to support higher-throughput workloads, making it relevant where shared filesystem access and scale matter.
• Resilience and recovery: Ceph can replicate data across devices, racks, and geographic locations, then redistribute it after hardware or connectivity failures. This helps organizations design for failures across more than one physical level, while leaving them responsible for operating the cluster.
• Kubernetes: The project recommends Rook to deploy Ceph in Kubernetes or connect an existing cluster; the Ceph CSI driver provisions block and file volumes. This gives Kubernetes teams a defined integration path, but still entails running Ceph.

Pricing

Ceph's free plan, Ceph, costs nothing and covers the open-source distributed storage software. There is no free trial because the software is free. The price removes a software license fee, not the commitment to provide and manage cluster hardware; block storage also depends on a running Ceph cluster. The production hardware guidance calls for at least three monitors, two managers, and three OSDs, with at least 10 Gb/s networking between hosts.

Platforms

Ceph supports API, Linux, self-hosted, and Windows environments. Organizations can install packages, container images, GitHub source clones, or tarballs; cephadm requires Python 3, systemd, and Podman or Docker. For Kubernetes deployments, Rook is the recommended route.

The project publishes a stable release each year, supports each series for approximately 24 months, and issues point releases every 4 to 6 weeks. For help, it directs users to documentation, the ceph-users mailing list, community channels, and the bug tracker. Suspected security vulnerabilities should be reported to its closed security mailing list at [email protected].

Who it's for

Ceph is a strong fit for businesses, cloud providers, universities, research institutions, and developers with the infrastructure expertise to operate distributed storage. Its unified object, block, and file capabilities are especially useful when those workloads need to coexist. Teams seeking storage without managing hardware and a cluster should look elsewhere.

Pros and cons

Pros

• One system for object, block, and file storage: This can reduce the need to assemble separate products for different storage workloads.
• Broad data-protection options: Replication across devices, racks, and geographic locations, plus recovery redistribution, supports deployments designed around hardware and connectivity failures.
• Free, open-source software: Organizations can use Ceph without a software plan charge and review its licensing terms.

Cons

• Operational overhead is substantial: Teams choose and manage the commodity hardware, and production guidance sets a multi-host and high-speed networking baseline.
• Block storage is cluster-dependent: RBD requires an operating Ceph cluster, which makes it unsuitable for teams looking for a standalone block-storage product.
• Cephadm has system prerequisites: Python 3, systemd, and Podman or Docker are required, adding constraints to that installation path.

Alternatives

OpenEBS is another free, open-source option if Kubernetes storage is the priority rather than Ceph's broader object, block, and file system.

SeaweedFS offers a free community-support plan for any cluster size, with public documentation and no guaranteed response time; consider it if that support model fits your needs.

VMware Workstation Pro is free for 64-bit Intel or AMD PCs running Windows or Linux hosts, a different choice for readers seeking host-based virtualization software.

Gluster is free, open-source software for Linux and self-hosted environments if you want another option in that category.

JuiceFS has a free self-hosted Community Edition with community support via GitHub and Discord; it may suit readers who prefer that support channel.

MinIO AIStor offers a free single-node deployment with its full feature set, with redistribution prohibited; it is an option for readers whose needs fit those terms.

MooseFS has a free Community plan with a single active master and single-parity erasure coding; choose it if those limits fit your deployment.

StarWind Virtual SAN has a free, self-supported plan with functionality limitations, so consider it if those constraints are acceptable.

Browse more options in Software-Defined Storage Software, Distributed File System Software, and Storage Management Software.

Verdict

Choose Ceph if your organization needs object, block, and file storage in one distributed system and has the people and hardware to operate it. Its breadth, replication, and recovery make it compelling for capable infrastructure teams; look elsewhere if you want managed storage or a block-storage option that does not depend on a running Ceph cluster.