juju-core 1.23-beta2

# juju-core 1.23-beta2

A new development release of Juju, juju-core 1.23-beta2, is now available.
This release replaces 1.23-beta1.

## Getting Juju

juju-core 1.23-beta2 is available for utopic and backported to earlier
series in the following PPA:

    https://launchpad.net/~juju/+archive/devel

Windows and OS X users will find installers at:

    https://launchpad.net/juju-core/+milestone/1.23-beta2

Development releases use the 'devel' simple-streams. You must configure
the 'agent-stream' option in your environments.yaml to use the matching
juju agents.

    agent-stream: devel

Upgrading from stable releases to development releases is not
supported. You can upgrade test environments to development releases
to test new features and fixes, but it is not advised to upgrade
production environments to 1.23-beta2.

## Notable Changes

  * Google Cloud Compute (GCE)
  * Service Leader Elections

### Google Cloud Compute (GCE)

You must specify 'region' in your environments.yaml file. For example:

    region: us-central1

If you extracted the 'private-key' by hand from the GCE project json,
change "\u003d" to "=".

You should not use the "europe-west1-a" availability zone. It has been
deprecated and will be shut down on March 29, 2015. See
https://cloud.google.com/compute/docs/release-notes#october152014. Juju
gets a list of availability zones at run-time through the GCE API, so
after that date it will not be a zone you may select anyway.

### Service Leader Elections

Services running in an environment bootstrapped with the
"leader-election" feature flag now have access to three new hook tools:

    is-leader - returns true only if the executing unit is guaranteed
        service leadership for the next 30s
    leader-get - as relation-get; accessible only within the service
    leader-set - as relation-set; will fail if not executed on leader

...and two new hooks:

    leader-elected - runs when the unit takes service leadership
    leader-settings-changed - runs when another unit runs leader-set

When a unit starts up, it will always run either leader-elected or
leader-settings-changed as soon as possible, delaying only doing so only
to run the install hook; complete any queued or in-flight operation; or
resolve a hook or upgrade error.

You can enable the "leader-election" feature flag in a new env by
bootstrapping with 'JUJU_DEV_FEATURE_FLAGS=leader-election' defined.

     JUJU_DEV_FEATURE_FLAGS=leader-election juju bootstrap

## Resolved issues

  * Juju-br0 is not configured correctly on maas machines without ethx
    interfaces
    Lp 1423372

  * Juju cannot deploy when distro-info-data gets a new series
    Lp 1427879

  * Juju backup fails when journal files are present
    Lp 1423936

Finally

We encourage everyone to subscribe the mailing list at
juju-dev@lists.canonical.com, or join us on #juju-dev on freenode.