Autoinstall

Manually installing operating systems across many bare-metal servers is a tedious process. Ubuntu provides an autoinstall framework through subiquity that enables automation of OS installs.

Configuration

We specify the autoinstall configuration using a YAML file included in the installation media. This YAML file must contain a root key of autoinstall with configuration keys included in this section. Many of the common errors is forgetting to nest all other keys under autoinstall or missing required keys; thus, we will include the root autoinstall: key in all examples.

Version

This future-proofing key is just used in case a new autoinstall.yaml formatting is released. Currently, it must be set to 1.

autoinstall:
  version: 1

Locale

The locale specifies information about user preferences for region-specific formatting such as numbers, currency, paper sizes, etc. You can find a list of enabled locales on a local linux system using:

$ locale --all-locales

Below is an example for setting United States English with UTF-8 encoding.

autoinstall:
  locale: "en_US.UTF-8"

Keyboard

TODO: Fill out from docs

autoinstall:
  keyboard:
    layout: us
    variant: ""
    toggle: null

Source

TODO: Fill out from docs

autoinstall:
  source:
    search_drivers: true
    id: ubuntu-server

Proxy

TODO: Fill out from docs

autoinstall:
  proxy: null

ssh

TODO: Fill out from docs

autoinstall:
  ssh:
    install-server: true
    authorized-keys: []
    allow-pw: false

Drivers

TODO: Fill out from docs

autoinstall:
  drivers:
    install: true

OEM

TODO: Fill out from docs

autoinstall:
  oem:
    install: false

Packages

TODO: Fill out from docs

  packages:
    - build-essential
    - git
    - nfs-common
    - nfs-kernel-server
    - curl
    - wget
    - cmake

Storage

Setting up the storage for the OS is where the most frustration can occur. The Ubuntu installation documentation only provides basic documentation and simple examples. We recommend reading about curtin, which is used to specify all steps of block device preparation.

Tip

If after a couple of tries of formatting the setup you want, it is much easier to remove this storage section and add it to interactive-sections. This will allow you to use the GUI to setup how you want your storage and you can see how curtin sets up this section. You can see this file by doing the following.

TODO: Check paths

Enter shell

Drop into the shell by going to Help in the top right (after finishing the storage section).

Find curtin logs

Navigate to the curtin configuration directory.

$ cd /var/log/installer/curtin-install

Open partition configuration

And open the partition config file.

$ nano sububiquity-curtin-partition.conf

Each item under the storage configuration specifies an action that curtin will take.

autoinstall:
  storage:
    config:
      # Action 1
      - key1: value1
        key2: value2
      # Action 2
      - key1: value1
        key2: value2

Each action has their set of keys that must be required, but each action requires a type and id. The type tells curtin the type of action we are describing and we give the result of that action a label called the id. For example, we can create a boot partition with the partition action type and refer to this partition action with the id of boot-partition when we format it. These ids are only ever used with curtin.

Warning

These actions are ran in order as they are specified. If you try to format a partition before defining that action, curtin will fail.

Disks

Every storage configuration starts by specifying the disks we will be working with during the installation.

autoinstall:
  storage:
    config:
      - type: disk
        id: disk0
        match:
          size: smallest
        ptable: gpt
        wipe: superblock-recursive
        preserve: false
        grub_device: false

Partitions

TODO: https://curtin.readthedocs.io/en/latest/topics/storage.html#partition-command

`/boot/efi`

autoinstall:
  storage:
    config:
      - type: partition
        id: efi-partition
        number: 1
        size: 1G
        device: disk0
        flag: boot
        preserve: false
        grub_device: true
        wipe: superblock

`/boot`

autoinstall:
  storage:
    config:
      - type: partition
        id: boot-partition
        number: 2
        size: 1G
        device: disk0
        preserve: false
        grub_device: false
        wipe: superblock

`SWAP`

autoinstall:
  storage:
    config:
      - type: partition
        id: swap-partition
        number: 3
        size: 8G
        device: disk0
        preserve: false
        grub_device: false
        wipe: superblock

Logical volume

autoinstall:
  storage:
    config:
      - type: partition
        id: pv0
        number: 4
        size: 500G
        device: disk0
        preserve: false
        grub_device: false
        wipe: superblock

Formatting

TODO: https://curtin.readthedocs.io/en/latest/topics/storage.html#format-command

autoinstall:
  storage:
    config:
      - type: format
        id: efi-format
        fstype: fat32
        volume: efi-partition
        preserve: false

Logical volumes

TODO:

autoinstall:
  storage:
    config:
      - type: lvm_volgroup
        id: vg0
        name: vg0
        devices:
          - pv0
        preserve: false

      # Logical volumes
      - type: lvm_partition
        id: root-lv
        name: root-lv
        volgroup: vg0
        size: 50G
        preserve: false
        wipe: superblock

Mounting

TODO: https://curtin.readthedocs.io/en/latest/topics/storage.html#mount-command

autoinstall:
  storage:
    config:
      - type: mount
        id: efi-mount
        path: /boot/efi
        device: efi-format

      - type: mount
        id: swap-mount
        path: ''
        device: swap-format

      - type: mount
        id: root-mount
        path: /
        device: root-format

Timezone

TODO: Fill out from docs

autoinstall:
  timezone: "US/Eastern"

Updates

TODO: Fill out from docs

autoinstall:
  updates: all

Shutdown

TODO: Fill out from docs

autoinstall:
  shutdown: reboot

Interactive sections

TODO: Fill out from docs

autoinstall:
  interactive-sections:
    - network
    - identity

Last updated on June 25, 2025