Using Juju with LXC Containers on a single machine in Ubuntu 14.04 LTS

Written by Kent Baxley, Canonical Field Engineer

Introduction

Juju is orchestration software from Canonical used to easily and quickly deploy and manage cloud services. For example, say you want to deploy a blog web site using the open source Wordpress application. This can be done in 3 easy steps with Juju:

1. Deploy the Wordpress Juju charm
2. This charm requires a database backend, deploy the MySQL Juju charm.
3. Associate both charms together.

This process illustrates the simplicity involved in deploying a new application in a matter of minutes. In addition, you can easily scale up or down in one simple step by adding or removing charm units.

Juju's  primary intent is to work either with various cloud providers or on bare metal in a MAAS environment.  However, Juju can be configured to run on a single machine via the Local Provider.

The Local Provider furnishes a way to use Juju to deploy services in Linux Containers (LXC) on your local machine instead of on a cloud or several bare metal systems.

What are some of the reasons for using the Local Provider?

• The Local Provider can be used as a test bed for users to experiment with Juju without having to spend money on hardware or cloud providers.
• It gives users a way to simulate a "production-like" cloud environment.  The user leverages cloud-images just like they would on a public cloud such as AWS, Azure, or Joyent.
• This helps speed up the process of evaluating or developing charms and charm bundles.
• A charm can be written in a local environment and be deployed straight to a cloud environment with little to no modifications.
• A user wishes to do demonstrations of juju on a portable device such as a laptop.
• A user many want to deploy several services on a single-server system. 

Configuring the Environment

This document will focus on using Ubuntu 14.04 LTS for the local Juju environment. The first thing to be done is connect the Ubuntu system to the Juju stable PPA.  This will provide the latest, stable versions of Juju.

To download the entire PDF, click Ubuntu document Using Juju with LXC Containers on a Single Machine in Ubuntu 14.04 LTS