RHCOS example

ign-example

apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
metadata:
  labels:
    machineconfiguration.openshift.io/role: master
  name: 99-ignition-disks
spec:
  config:
    ignition:
      version: 2.2.0
    storage:
      disks:
        - device: /dev/xvdb
          partitions:
            - label: var-log
              number: 0
              size_mib: 0
      filesystems:
        - device: /dev/disk/by-partlabel/var-log
          format: xfs
          label: var-log
          wipe_filesystem: true
    systemd:
      units:
        - contents: |
            [Unit]
            Before=local-fs.target
            [Mount]
            Where=/var/log
            What=/dev/disk/by-partlabel/var-log
            [Install]
            WantedBy=local-fs.target
          enabled: true
          name: var-log.mount