Create MOSK host profiles

Different types of MOSK nodes require differently configured host storage. This section describes how to create custom host profiles for different types of MOSK nodes.

You can create custom profiles for managed clusters using Container Cloud API.

Since MOSK 22.4, you can use flexible size units throughout bare metal host profiles. For example, you can now use either sizeGiB: 0.1 or size: 100Mi when specifying a device size.

Mirantis recommends using only one parameter name type and units throughout the configuration files. If both sizeGiB and size are used, sizeGiB is ignored during deployment and the suffix is adjusted accordingly. For example, 1.5Gi will be serialized as 1536Mi. The size without units is counted in bytes. For example, size: 120 means 120 bytes.


All data will be wiped during cluster deployment on devices defined directly or indirectly in the fileSystems list of BareMetalHostProfile. For example:

  • A raw device partition with a file system on it

  • A device partition in a volume group with a logical volume that has a file system on it

  • An mdadm RAID device with a file system on it

  • An LVM RAID device with a file system on it

The wipe field is always considered true for these devices. The false value is ignored.

Therefore, to prevent data loss, move the necessary data from these file systems to another server beforehand, if required.

To create MOSK bare metal host profiles:

  1. Log in to the local machine where you management cluster kubeconfig is located and where kubectl is installed.


    The management cluster kubeconfig is created automatically during the last stage of the management cluster bootstrap.

  2. Create a new bare metal host profile for MOSK compute nodes in a YAML file under the templates/bm/ directory.

  3. Edit the host profile using the example template below to meet your hardware configuration requirements:

    kind: BareMetalHostProfile
      name: <PROFILE_NAME>
      namespace: <PROJECT_NAME>
      # From the HW node, obtain the first device, which size is at least 60Gib
      - device:
          workBy: "by_id,by_wwn,by_path,by_name"
          minSize: 60Gi
          type: ssd
          wipe: true
        - name: bios_grub
          - bios_grub
          size: 4Mi
          wipe: true
        - name: uefi
          - esp
          size: 200Mi
          wipe: true
        - name: config-2
          size: 64Mi
          wipe: true
        # This partition is only required on compute nodes if you plan to
        # use LVM ephemeral storage.
        - name: lvm_nova_part
          wipe: true
          size: 100Gi
        - name: lvm_root_part
          size: 0
          wipe: true
      # From the HW node, obtain the second device, which size is at least 60Gib
      # If a device exists but does not fit the size,
      # the BareMetalHostProfile will not be applied to the node
      - device:
          workBy: "by_id,by_wwn,by_path,by_name"
          minSize: 60Gi
          type: ssd
          wipe: true
      # From the HW node, obtain the disk device with the exact name
      - device:
          workBy: "by_id,by_wwn,by_path,by_name"
          minSize: 60Gi
          wipe: true
        - name: lvm_lvp_part
          size: 0
          wipe: true
      # Example of wiping a device w\o partitioning it.
      # Mandatory for the case when a disk is supposed to be used for Ceph back end
      # later
      - device:
          workBy: "by_id,by_wwn,by_path,by_name"
          wipe: true
      - fileSystem: vfat
        partition: config-2
      - fileSystem: vfat
        mountPoint: /boot/efi
        partition: uefi
      - fileSystem: ext4
        logicalVolume: root
        mountPoint: /
      - fileSystem: ext4
        logicalVolume: lvp
        mountPoint: /mnt/local-volumes/
      - name: root
        size: 0
        vg: lvm_root
      - name: lvp
        size: 0
        vg: lvm_lvp
      postDeployScript: |
        #!/bin/bash -ex
        echo $(date) 'post_deploy_script done' >> /root/post_deploy_done
      preDeployScript: |
        #!/bin/bash -ex
        echo $(date) 'pre_deploy_script done' >> /root/pre_deploy_done
      - devices:
        - partition: lvm_root_part
        name: lvm_root
      - devices:
        - partition: lvm_lvp_part
        name: lvm_lvp
        - GRUB_DISABLE_RECOVERY="true"
        - GRUB_TIMEOUT=20
          kernel.panic: "900"
          kernel.dmesg_restrict: "1"
          kernel.core_uses_pid: "1"
          fs.file-max: "9223372036854775807"
          fs.aio-max-nr: "1048576"
          fs.inotify.max_user_instances: "4096"
          vm.max_map_count: "262144"
  4. Add or edit the mandatory parameters in the new BareMetalHostProfile object. For the parameters description, see Container Cloud API: BareMetalHostProfile spec.

  5. Add the bare metal host profile to your management cluster:

    kubectl --kubeconfig <pathToManagementClusterKubeconfig> -n <projectName> apply -f <pathToBareMetalHostProfileFile>
  6. If required, further modify the host profile:

    kubectl --kubeconfig <pathToManagementClusterKubeconfig> -n <projectName> edit baremetalhostprofile <hostProfileName>
  7. Repeat the steps above to create host profiles for other OpenStack node roles such as control plane nodes and storage nodes.

Now, proceed to Enable huge pages in a host profile.