Mirantis Container Cloud (MCC) becomes part of Mirantis OpenStack for Kubernetes (MOSK)!
Starting with MOSK 25.2, the MOSK documentation set covers all product layers, including MOSK management (formerly Container Cloud). This means everything you need is in one place. Some legacy names may remain in the code and documentation and will be updated in future releases. The separate Container Cloud documentation site will be retired, so please update your bookmarks for continued easy access to the latest content.
MOSK management deploys Ceph on MOSK
using Helm charts with the following components:
Rook Ceph Operator
A storage orchestrator that deploys Ceph on top of a Kubernetes cluster. Also
known as Rook or RookOperator. Rook operations include:
Deploying and managing a Ceph cluster based on provided Rook CRs such as
CephCluster, CephBlockPool, CephObjectStore, and so on.
Orchestrating the state of the Ceph cluster and all its daemons.
Ceph cluster custom resource (Ceph cluster CR)
Represents the customization of a Kubernetes installation and allows you to
define the required Ceph configuration before deployment. For example, you
can define the failure domain, Ceph pools, Ceph node roles, number of Ceph
components such as Ceph OSDs, and so on. The Ceph cluster CR differs in
MOSK releases:
MOSK 25.2 and later
The MiraCeph CR that is managed by ceph-controller on the
MOSK cluster.
MOSK 25.1 and earlier
The KaaSCephCluster CR that is managed by ceph-kcc-controller on
the management cluster.
Ceph Controller
A Kubernetes controller that obtains the parameters from
MOSK management through a CR, creates CRs for Rook and
updates its CR status based on the Ceph cluster deployment progress. It
creates users, pools, and keys for OpenStack and Kubernetes and provides Ceph
configurations and keys to access them. Also, Ceph Controller eventually
obtains the data from the OpenStack Controller (Rockoon) for the Keystone
integration and updates the Ceph Object Gateway services configurations to use
Kubernetes for user authentication.
The Ceph Controller operations include:
Transforming user parameters from the MOSK Ceph CR into
Rook CRs and deploying a Ceph cluster using Rook.
Providing integration of the Ceph cluster with Kubernetes.
Providing data for OpenStack to integrate with the deployed Ceph cluster.
Ceph Status Controller
MOSK 25.2 and later
A Kubernetes controller that collects all valuable parameters from the current
Ceph cluster, its daemons, and entities and exposes them into the
MiraCephHealth status. Ceph Status Controller operations include:
Collecting all statuses from a Ceph cluster and corresponding Rook CRs.
Collecting additional information on the health of Ceph daemons.
Provides information to the status section of the MiraCephHealth
CR.
MOSK 25.1 and earlier
A Kubernetes controller that collects all valuable parameters from the current
Ceph cluster, its daemons, and entities and exposes them into the
KaaSCephCluster status. Ceph Status Controller operations include:
Collecting all statuses from a Ceph cluster and corresponding Rook CRs.
Collecting additional information on the health of Ceph daemons.
Provides information to the status section of the KaaSCephCluster
CR.
Ceph Request Controller
A Kubernetes controller that obtains the parameters from
MOSK management through a CR and manages Ceph OSD lifecycle
management (LCM) operations. It allows for a safe Ceph OSD removal from the
Ceph cluster. Ceph Request Controller operations include:
Providing an ability to perform Ceph OSD LCM operations.
Obtaining specific CRs to remove Ceph OSDs and executing them.
Pausing the regular Ceph Controller reconciliation until all requests are
completed.
A typical Ceph cluster consists of the following components:
Ceph Managers:
MOSK 22.5 and later
Two Ceph Managers
MOSK 22.4 and earlier
One Ceph Manager
Three or, in rare cases, five Ceph Monitors
Ceph Object Gateway (radosgw). Mirantis recommends having three or more
radosgw instances for HA.
Ceph OSDs. The number of Ceph OSDs may vary depending on deployment needs.
Warning
A Ceph cluster with 3 Ceph nodes does not provide hardware fault
tolerance and is not eligible for recovery operations, such as a disk or
an entire Ceph node replacement.
A Ceph cluster uses the replication factor that equals 3. If the number of
Ceph OSDs is less than 3, a Ceph cluster moves to the degraded state with
the write operations restriction until the number of alive Ceph OSDs
equals the replication factor again.
The placement of Ceph Monitors and Ceph Managers is defined in the following
CR:
MOSK 25.2 and later
MiraCeph
MOSK 25.1 and earlier
KaaSCephCluster
The following diagram illustrates the way a Ceph cluster is deployed in
MOSK:
MOSK 25.2 and later
MOSK 25.1 and earlier
The following diagram illustrates the processes within a deployed Ceph cluster: