Add a Ceph cluster

After you add machines to your new bare metal managed cluster as described in Add a machine, create a Ceph cluster on top of this managed cluster using the Mirantis Container Cloud web UI.

For an advanced configuration through the KaaSCephCluster CR, see Mirantis Container Cloud Operations Guide: Ceph advanced configuration. To configure Ceph Controller through Kubernetes templates to manage Ceph nodes resources, see Mirantis Container Cloud Operations Guide: Enable Ceph tolerations and resources management.

The procedure below enables you to create a Ceph cluster with minimum three Ceph nodes that provides persistent volumes to the Kubernetes workloads in the managed cluster.

To create a Ceph cluster in the managed cluster:

  1. Log in to the Container Cloud web UI with the m:kaas:namespace@operator or m:kaas:namespace@writer permissions.

  2. Switch to the required project using the Switch Project action icon located on top of the main left-side navigation panel.

  3. In the Clusters tab, click the required cluster name. The Cluster page with the Machines and Ceph clusters lists opens.

  4. In the Ceph Clusters block, click Create Cluster.

  5. Configure the Ceph cluster in the Create New Ceph Cluster wizard that opens:

    Create new Ceph cluster

    Section

    Parameter name

    Description

    General settings

    Name

    The Ceph cluster name.

    Cluster Network

    Replication network for Ceph OSDs. Must contain the CIDR definition and match the corresponding values of the cluster L2Template object or the environment network values.

    Public Network

    Public network for Ceph data. Must contain the CIDR definition and match the corresponding values of the cluster L2Template object or the environment network values.

    Enable OSDs LCM

    Select to enable LCM for Ceph OSDs.

    Machines / Machine #1-3

    Select machine

    Select the name of the Kubernetes machine that will host the corresponding Ceph node in the Ceph cluster.

    Manager, Monitor

    Select the required Ceph services to install on the Ceph node.

    Devices

    Select the disk that Ceph will use.

    Warning

    Do not select the device for system services, for example, sda.

    Enable Object Storage

    Select to enable the single-instance RGW Object Storage.

  6. To add more Ceph nodes to the new Ceph cluster, click + next to any Ceph Machine title in the Machines tab. Configure a Ceph node as required.

    Warning

    Do not add more than 3 Manager and/or Monitor services to the Ceph cluster.

  7. After you add and configure all nodes in your Ceph cluster, click Create.

  8. Open the KaaSCephCluster CR for editing as described in Mirantis Container Cloud Operations Guide: Ceph advanced configuration.

  9. Verify that the following snippet is present in the KaaSCephCluster configuration:

    network:
      clusterNet: 10.10.10.0/24
      publicNet: 10.10.11.0/24
    
  10. Configure the pools for Image, Block Storage, and Compute services.

    Note

    Ceph validates the specified pools. Therefore, do not omit any of the following pools.

    spec:
      pools:
        - default: true
          deviceClass: hdd
          name: kubernetes
          replicated:
            size: 3
          role: kubernetes
        - default: false
          deviceClass: hdd
          name: volumes
          replicated:
            size: 3
          role: volumes
        - default: false
          deviceClass: hdd
          name: vms
          replicated:
            size: 3
          role: vms
        - default: false
          deviceClass: hdd
          name: backup
          replicated:
            size: 3
          role: backup
        - default: false
          deviceClass: hdd
          name: images
          replicated:
            size: 3
          role: images
        - default: false
          deviceClass: hdd
          name: other
          replicated:
            size: 3
          role: other
    

    Note

    Since MOSK 22.1, omit the pool with role other. It is not required for Ceph cluster configuration.

    Each Ceph pool, depending on its role, has a default targetSizeRatio value that defines the expected consumption of the total Ceph cluster capacity. The default ratio values for MOSK pools are as follows:

    • 20.0% for a Ceph pool with role volumes

    • 40.0% for a Ceph pool with role vms

    • 10.0% for a Ceph pool with role images

    • 10.0% for a Ceph pool with role backup

  11. Once all pools are created, verify that an appropriate secret required for a successful deployment of the OpenStack services that rely on Ceph is created in the openstack-ceph-shared namespace:

    kubectl -n openstack-ceph-shared get secrets openstack-ceph-keys
    

    Example of a positive system response:

    NAME                  TYPE     DATA   AGE
    openstack-ceph-keys   Opaque   7      36m
    
  12. Verify your Ceph cluster as described in Mirantis Container Cloud Operations Guide: Verify Ceph.