Individual Provider Block Storage vs. Ceph

Storage as a Cloud Feature or as a Controllable Platform

Persistent storage is one of the most inconspicuous yet powerful layers of modern platforms. It determines whether applications remain scalable, whether data is portable, and how costly a later change of direction will be. Block storage from cloud providers often appears as a neutral infrastructure feature. In reality, it is deeply embedded in the respective platform logic.

Provider block storage and Ceph solve the same fundamental problem: reliably storing stateful data. Architecturally, however, they represent two opposing models. One ties storage to the cloud. The other makes it an independent, controllable platform component.

Provider Block Storage: Storage as Part of the Cloud Platform

Block storage offerings from cloud providers are optimized for quick availability. Volumes can be attached to virtual machines or Kubernetes nodes with just a few clicks. Snapshots, replication, and basic failure scenarios are integrated, with operation and availability fully managed by the provider.

For many workloads, this is sufficient—especially when architecture, runtime environment, and data storage remain within a single cloud. The entry is simple, and the operational effort is minimal.

This form of storage, however, is not an independent layer.

Platform Logic Instead of Neutral Storage Layer

Provider block storage is part of the respective cloud platform logic. Volumes are bound to zones, performance profiles are controlled via predefined classes, and replication follows internal provider architectures. Kubernetes uses these resources via CSI drivers, but remains bound to the limitations of the respective storage offering.

A change of environment almost always means active data migration. This occurs under load, is time-critical, and incurs additional costs. Architectural decisions at the storage level thus have long-term and often irreversible effects.

Storage is consumed here—not designed.

Ceph: Storage as Independent Infrastructure

Ceph addresses storage from a different perspective. As a distributed open-source system, Ceph provides block storage via RBD, which integrates seamlessly with Kubernetes. Replication, fault tolerance, and self-healing are integral parts of the system.

Storage thus becomes an independent platform component—regardless of whether Kubernetes is operated on-premises, in a European cloud, or distributed across multiple locations. Data is not located in zones but in a cluster.

Ceph is not cloud storage. It is storage infrastructure.

Architectural Control as Core Difference

The decisive difference lies in architectural control. Ceph fully abstracts hardware and distributes data across a scalable cluster. Capacity and performance grow horizontally. Redundancy, replication, and fault tolerance are defined by policies—not by SKU selection or provider limits.

For Kubernetes platforms, this creates a persistent storage layer that is not tied to individual nodes, zones, or clouds. Stateful workloads remain portable. Clusters can be expanded, moved, or re-established without rethinking data storage.

This is structurally not possible with provider block storage.

Operational Maturity Instead of Convenience

This approach requires operational maturity. Ceph is not a “fire-and-forget” service. Network design, hardware selection, monitoring, upgrades, and lifecycle management are part of the responsibility. Errors in architecture have immediate effects.

In return, a storage system is created that is long-term plannable: technically transparent, auditable, and independent of short-term price or product decisions by individual providers. Optimization means better architecture—not higher service tiers.

Complexity is not avoided here but controlled.

Relevance for Kubernetes Platforms

Especially in Kubernetes environments with stateful applications, regulatory requirements, or European infrastructure demands, the assessment shifts significantly. Provider block storage simplifies entry but firmly ties storage to the platform.

Ceph decouples data storage from compute and cloud. Storage becomes reusable, consistent, and usable across multiple environments. For platforms intended to be operated and developed long-term, this is a decisive difference.

Condensed Comparison

When Each Approach Makes Sense

Provider block storage is sensible for:

• simple cloud workloads
• quick proofs of concept
• low data portability requirements
• focus on minimal operational effort

Ceph is sensible for:

• Kubernetes-centric platform architectures
• stateful applications
• regulated or sovereign infrastructures
• multi-cluster or hybrid setups
• long-term storage strategies

Conclusion

Persistent data is not a byproduct of the platform. They determine how flexible an architecture remains—today and in the coming years.

Provider block storage subordinates storage to the cloud. Ceph makes storage an independent, designable infrastructure component.

The difference is not primarily technical but strategic. Those who bind storage to a platform also bind their data. Those who control storage retain freedom—even if cloud, location, or operating model change.