Enable LVM ephemeral storage

Available since MOS 21.2 TechPreview

Note

Consider this section as part of Deploy an OpenStack cluster.

This section instructs you on how to configure LVM as back end for the VM disks and ephemeral storage.

To enable LVM ephemeral storage:

  1. In BareMetalHostProfile in the spec:volumeGroups section, add the following configuration for the OpenStack compute nodes:

    spec:
      devices:
        - device:
            byName: /dev/nvme0n1
            minSizeGiB: 30
            wipe: true
          partitions:
            - name: lvm_nova_vol
              sizeGiB: 0
              wipe: true
      volumeGroups:
        - devices:
          - partition: lvm_nova_vol
          name: nova-vol
      logicalVolumes:
        - name: nova-fake
          vg: nova-vol
          sizeGiB: 0.1
      fileSystems:
        - fileSystem: ext4
          logicalVolume: nova-fake
          mountPoint: /nova-fake
    

    Note

    Due to a limitation, it is not possible to create volume groups without logical volumes and formatted partitions. Therefore, set the logicalVolumes:name, fileSystems:logicalVolume, and fileSystems:mountPoint parameters to nova-fake.

    For details about BareMetalHostProfile, see Mirantis Container Cloud Operations Guide: Create a custom bare metal host profile.

  2. Configure the OpenStackDeployment CR to deploy OpenStack with LVM ephemeral storage. For example:

    spec:
      features:
        nova:
          images:
            backend: lvm
            lvm:
              volume_group: "nova-vol"
    
  3. Optional. Enable encryption for the LVM ephemeral storage by adding the following metadata in the OpenStackDeployment CR:

    spec:
      features:
        nova:
          images:
            encryption:
              enabled: true
              cipher: "aes-xts-plain64"
              key_size: 256
    

    Caution

    Both live and cold migrations are not supported for such instances.