Upgrades

cOS vanilla images by default are picking upgrades by the standard upgrade channel. It means it will always get the latest published cOS version by our CI.

However, it’s possible to tweak the default behavior of elemental upgrade to point to a specific docker image/tag, or a different release channel.

By default, cos derivatives if not specified will point to latest cos-toolkit. To override, you need to or overwrite the content of /system/oem/02_upgrades.yaml or supply an additional one, e.g. /system/oem/03_upgrades.yaml in the final image, see the default here.

Configuration

elemental upgrade during start reads the cOS configuration file and allows to tweak the following:

# Tweak the package to upgrade to, or the docker image (full reference)
ELEMENTAL_UPGRADE_IMAGE=system/cos
# Turn on/off channel upgrades. If disabled, UPGRADE_IMAGE should be a full reference to a container image
ELEMENTAL_CHANNEL_UPGRADES=true
# Disable mtree verification. Enabled by default
ELEMENTAL_NO_VERIFY=true
# Specify a separate recovery image (defaults to UPGRADE_IMAGE)
ELEMENTAL_RECOVERY_IMAGE=recovery/cos

elemental upgrade also reads its configuration from /etc/cos-upgrade-image if the file is present in the system.

Specifically, it allows to configure:

• ELEMENTAL_UPGRADE_IMAGE: A container image reference ( e.g. registry.io/org/image:tag ) or a luet package ( e.g. system/cos )
• ELEMENTAL_CHANNEL_UPGRADES: Boolean indicating wether to use channel upgrades or not. If it is disabled UPGRADE_IMAGE should refer to a container image, e.g. registry.io/org/image:tag
• ELEMENTAL_NO_VERIFY: Turns off or on mtree verification.
• ELEMENTAL_RECOVERY_IMAGE: Allows to specify a different image for the recovery partition. Similarly to UPGRADE_IMAGE needs to be either an image reference or a package.

Changing the default release channel

Release channels are standard luet repositories. To change the default release channel, create a /etc/luet/luet.yaml configuration file pointing to a valid luet repository:

# For a full reference, see:
# https://luet-lab.github.io/docs/docs/getting-started/#configuration
logging:
  color: false
  enable_emoji: false
general:
    debug: false
    spinner_charset: 9
repositories:
- name: "sampleos"
  description: "sampleOS"
  type: "docker"
  enable: true
  cached: true
  priority: 1
  verify: false
  urls:
  - "quay.io/costoolkit/releases-green"