The major new features in this release are summarised below. If you're new to Juju, begin by going through our Getting started guide first.
For details on these features, and other improvements not listed here, see the 2.3 release notes.
Persistent storage enables operators to manage the life-cycle of storage independently of Juju machines. See Using Juju storage for a complete breakdown of how persistent storage, also called dynamic storage, fits in with legacy Juju storage.
Cross model relations make centralised management of multiple models a reality by allowing applications in separate models to form relations between one another. This feature also works across multiple controllers. See Cross model relations for more information and examples.
Fan networking leads to the reconfiguration of an IPv4 address space such that network connectivity among containers running on separate hosts becomes possible. Applied to Juju, this allows for the seamless interaction between deployed applications running within LXD containers on separate Juju machines. Read Juju and Fan networking for more on this exciting topic.
You can now recycle existing machines instead of having new ones created. It is also possible to map specific machines to machines configured in the bundle.
A bundle declaration can be placed on top of a base bundle to override elements of the latter. These are bonafide bundle files, called "overlay bundles", that can do anything a normal bundle can do. They can also remove applications from the base bundle. See Overlay bundles.