Ceph architecture

Operating a Charmed Ceph cluster involves managing distributed storage components orchestrated by Juju. This guide provides an overview of the general Ceph architecture with some of the components that can be deployed.

Architectural overview

The diagram below depicts a typical Charmed Ceph deployment with ceph-radosgw and ceph-fs deployed. Note that the Charmed Ceph ecosystem is flexible and can be tailored to a specific use case, so the architecture here is just an example.

Components

• Admin workstation: operators’ machine used to manage and monitor the deployment.
• Juju controller: Orchestrates the Juju model that contains all Ceph services.
• ceph-mon: Ceph Monitor (MON) daemons; usually deployed as three units in an HA setup.
• ceph-osd: Hosts Ceph Object Storage Daemons (OSDs); each unit manages one or more data disks.
• ceph-radosgw: RGW (object‑storage) service; typically deployed in a highly‑available configuration with at least three units.
• ceph-fs: Metadata Server (MDS) daemons for CephFS; typically deployed in an HA set of at least three units.
• Client workloads: Consume Ceph storage via RBD block devices, RGW object buckets, or CephFS shared filesystems.