Juju 2.9-rc12 Release Notes

The Juju team is proud to release Juju 2.9-rc12!

The new operator pattern continues to gain maturity.

File resources in sidecar charms

Sidecar charms can now access file resources using resource-get.
These can be copied to the workload container using the Pebble file API.

Assume a charm declares a file resource called test-file.

    type: file
    filename: filename.txt
    description: A test file

Sample charm code:

    def _on_snappass_pebble_ready(self, event):
        container = self.unit.containers["redis"]
        test_file = self.model.resources.fetch("test-file")
        container.push(str(test_file), test_file.read_bytes(), make_dirs=True)
        logger.info("files at %s are %s", str(target_dir), container.list_files(str(target_dir)))

        if self._is_running(container, "redis"):
            logger.info("redis already started")

This release also includes important fixes

  • LP#1925427 - Cannot deploy postgresql-k8s charm from charmhub

Additional bugs fixed can be found in the milestone page.

Other recent fixes in the 2.9 RC Series


  • LP#1916621 - Ingress rules are removed if pod spec changes


  • LP#1915418 - network-get format yaml keys differ from format json
  • LP#1923141 - juju dashboard command returns wrong IP for microk8s


  • LP #1921722 - Migration fails with different metadata name to charm URL name
  • LP #1922098 - Juju 2.9-rc8 breaks manual provider spaces
  • canonical/pebble PR #24 - Change the Pebble layer configuration format for sidecar charms: environment variables now use a plain YAML object rather than a list of single-item objects.

Full details of releases in the series are available via the series page.

Known Issues

Dashboard on kubernetes

On k8s installations based on minikube or kind or rancher, the Juju Dashboard will not be able to be served because there’s no direct access to the controller service out of the box. A fix is being investigated.

How do I install Juju?

The best way to get your hands on this release of Juju is to install it as a snap:

sudo snap install juju --classic

Other packages are available for a variety of platforms, including Windows and macOS. Refer to the full Juju installation documentation.

Those subscribed to a snap channel should be automatically upgraded. If you’re using the PPA or Homebrew for macOS, you should see an upgrade available.

How do I upgrade?

Upgrading Juju is a multi-step process:

  • upgrade the client (the Juju binary that you interact with on the command-line)
  • (recommended) verify that the client upgrade was successful
  • (recommended) back up the controller
  • upgrade the controller
  • upgrade models

Upgrade the client

If you’ve installed Juju via the snap, your Juju will automatically be installed overnight. To force the update, run:

snap refresh juju 
Upgrading the Juju client through other channels

If you’re using the PPA:

sudo apt update
sudo apt upgrade

On Homebrew for macOS:

brew update
brew upgrade

Check version

To prevent any confusion in later steps, ensure that you’re using the new Juju version.

juju version
What to do if Juju reports an old version

Check your $PATH environment variable and that you’ve installed the new version correctly.

On Linux and macOS, use the env command to inspect the environment. On MS Windows, use SET.

Backing up

The controller state can be saved to allow for recovery in case the upgrade process encounters a serious error.

juju create-backup

Upgrading controllers

Juju includes a command that instructs the controller to upgrade itself to the latest version.

juju upgrade-controller
How to upgrade the controller

First, check that you’re interacting with the intended controller. The juju models command reports the current controller on the first line.

juju models

To verify what will occur, use the --dry-run option.

juju upgrade-controller --dry-run

When you’re happy, omit the flag:

juju upgrade-controller

Upgrade models

Your models remain at the same version until you have explicitly told Juju to upgrade them.

juju upgrade-model
How to upgrade your model(s)

Check that you’re operating in the correct model. juju model highlights the current model with an asterisk:

juju models

To verify what will occur, use the --dry-run option.

juju upgrade-juju --dry-run

When you’re happy, omit the flag:

juju upgrade-juju

Further instructions

Juju’s documentation pages provide detailed information about the upgrade process:

Feedback Appreciated!

We encourage everyone to let us know how you’re using Juju. Please ask questions on on Discourse, send us a message to our Twitter account @juju_devops, tweet using the hashtag #juju_devops, and chat with us at #juju on Freenode.