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Local Storage

Jetlag can prepare disks and optionally install the OpenShift Local Storage Operator (LSO) on control-plane and worker nodes during cluster deployment. Disk preparation (wiping, partitioning, LVM setup) is triggered by populating device lists and handled via Ignition at node boot time. LSO installation is controlled independently by setup_lso and creates LocalVolume resources post-install.

Table of Contents

Variables

Disk preparation variables are defined in ansible/roles/configure-local-storage/defaults/main.yml. LSO and LocalVolume variables are in the post-install role defaults. Override them in the Extra vars section of ansible/vars/all.yml.

Control-plane / SNO disk preparation

Populating any device list below triggers Ignition-based disk wiping/partitioning at node boot.

Variable Default Description
controlplane_localstorage_lvm_devices [] List of disks to partition and include in the LVM volume group. Empty list disables LVM setup
controlplane_localstorage_disk_devices [] List of disks to wipe and expose as raw block devices
controlplane_localstorage_lv_count 10 Number of thin logical volumes to create in the LVM volume group
controlplane_localstorage_lv_size 100G Size of each thin logical volume

Worker node disk preparation

Variable Default Description
worker_localstorage_lvm_devices [] List of disks to partition and include in the LVM volume group on worker nodes. Empty list disables LVM setup
worker_localstorage_disk_devices [] List of disks to wipe and expose as raw block devices on worker nodes
worker_localstorage_lv_count 10 Number of thin logical volumes to create in the LVM volume group
worker_localstorage_lv_size 100G Size of each thin logical volume

LSO installation (post-install)

Variable Default Description
setup_lso false Install the Local Storage Operator and create LocalVolume resources for any populated device lists

LocalVolume volume modes

Variable Default Description
localstorage_lvm_volume_mode Filesystem volumeMode for the localvolume-lvm resource (Filesystem or Block)
localstorage_disk_volume_mode Block volumeMode for the localvolume-disk resource (Filesystem or Block)
localstorage_disk_force_wipe true Sets forceWipeDevicesAndDestroyAllData on the localvolume-disk resource, causing LSO to wipe any existing filesystem signatures on the devices

etcd on NVMe (related, but separate from LSO)

Variable Default Description
controlplane_etcd_on_nvme false Partition an NVMe disk at boot to host etcd and container storage
controlplane_nvme_device /dev/nvme0n1 NVMe device to partition for etcd

Disk types

LVM disks

Disks listed in controlplane_localstorage_lvm_devices (or worker_localstorage_lvm_devices for workers) are handled at node boot via an Ignition-embedded script:

  1. Each disk is wiped and receives a partition labeled LS0, LS1, etc.
  2. All partitions are combined into a single LVM volume group vg_ls.
  3. A thin pool lv_tp_ls is created using 99% of the volume group.
  4. controlplane_localstorage_lv_count thin logical volumes (lv_cp_tv00, lv_cp_tv01, …) are carved from the pool at controlplane_localstorage_lv_size each.

Setting controlplane_localstorage_lvm_devices to an empty list disables steps 1–4.

Plain disks

Disks listed in controlplane_localstorage_disk_devices (or worker_localstorage_disk_devices) are wiped at node boot (wipeTable: true) with no partitions created. They are exposed directly to LSO as raw block devices via the localvolume-disk resource.

LocalVolume resources

LocalVolume resources can be created. Each is applied only when its condition is met.

Resource Storage class Default mode Condition
localvolume-lvm localstorage-sc Filesystem controlplane_localstorage_lvm_devices or worker_localstorage_lvm_devices is non-empty
localvolume-disk localstorage-disk-sc Block controlplane_localstorage_disk_devices or worker_localstorage_disk_devices is non-empty

When localstorage_lvm_volume_mode or localstorage_disk_volume_mode is set to Block, the fsType field is omitted from the resource since block devices are not pre-formatted.

Configuration examples

Control-plane with LVM only

Three LVM logical volumes on a single disk, wiped at boot and exposed via LSO as a filesystem storage class:

controlplane_localstorage_lvm_devices:
  - /dev/disk/by-path/pci-0000:4a:00.0-scsi-0:0:2:0
controlplane_localstorage_lv_count: 3
controlplane_localstorage_lv_size: 500G
setup_lso: true

Control-plane with block disks only

controlplane_localstorage_disk_devices:
  - /dev/disk/by-path/pci-0000:4a:00.0-scsi-0:0:2:0
  - /dev/disk/by-path/pci-0000:4a:00.0-scsi-0:0:3:0
setup_lso: true

Control-plane with LVM and block disks

LVM volumes on one disk, plus two additional raw disks exposed as block devices:

controlplane_localstorage_lvm_devices:
  - /dev/disk/by-path/pci-0000:4a:00.0-scsi-0:0:2:0
controlplane_localstorage_lv_count: 10
controlplane_localstorage_lv_size: 100G
controlplane_localstorage_disk_devices:
  - /dev/disk/by-path/pci-0000:4a:00.0-scsi-0:0:3:0
localstorage_disk_volume_mode: Block
setup_lso: true

This creates both localvolume-lvm (storage class localstorage-sc) and localvolume-disk (storage class localstorage-disk-sc).

Workers with LVM

worker_localstorage_lvm_devices:
  - /dev/disk/by-path/pci-0000:4a:00.0-scsi-0:0:2:0
worker_localstorage_lv_count: 10
worker_localstorage_lv_size: 200G
setup_lso: true

Wipe only, no LSO

Wipe and partition disks at boot time without installing the Local Storage Operator. Useful when preparing disks for other storage backends (e.g., ODF) or for clean disk state:

controlplane_localstorage_disk_devices:
  - /dev/disk/by-path/pci-0000:4a:00.0-scsi-0:0:2:0
  - /dev/disk/by-path/pci-0000:4a:00.0-scsi-0:0:3:0

Omitting setup_lso (or setting it to false) skips LSO installation. The disks are wiped at node boot via Ignition but no LocalVolume resources are created.