Create LVM volume groups on top of RAID devices

TechPreview

You can configure an LVM volume group on top of mdadm-based RAID devices as physical volumes using the BareMetalHostProfile resource. List the required RAID devices in a separate field of the volumeGroups definition within the storage configuration of BareMetalHostProfile.

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.

Warning

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.

The following example illustrates an extract of BaremetalHostProfile with a volume group named lvm_nova to be created on top of an mdadm-based RAID device raid1:

...
devices:
  - device:
      workBy: "by_id,by_wwn,by_path,by_name"
      minSize: 60Gi
      type: ssd
      wipe: true
    partitions:
      - name: bios_grub
        partflags:
          - bios_grub
        size: 4Mi
      - name: uefi
        partflags:
          - esp
        size: 200Mi
      - name: config-2
        size: 64Mi
  - device:
      workBy: "by_id,by_wwn,by_path,by_name"
      minSize: 30Gi
      type: ssd
      wipe: true
    partitions:
      - name: md0_part1
  - device:
      workBy: "by_id,by_wwn,by_path,by_name"
      minSize: 30Gi
      type: ssd
      wipe: true
    partitions:
      - name: md0_part2
softRaidDevices:
  - devices:
      - partition: md0_part1
      - partition: md0_part2
    level: raid1
    metadata: "1.0"
    name: /dev/md0
volumeGroups:
  - devices:
      - softRaidDevice: /dev/md0
    name: lvm_nova
...