Juju Quick Start

These instructions will help you deploy your first charm with Juju to a MAAS cluster.

A few assumptions are made:

• You have a MAAS cluster set-up, and you have at least 2 nodes enlisted with it.

• You’re running MAAS on your local machine. If not you’ll need to adjust some of the URLs mentioned accordingly.

• You’re running Juju from the PPA (ppa:juju/pkgs) or from a branch of lp:juju. At the time of writing MAAS support had not made it into the main Ubuntu archives. However, following the release of Ubuntu Precise, all the necessary package revisions will be in main.

  If you’re using a branch, note that you’ll need to set PYTHONPATH carefully to ensure you use the code in the branch.

Your API key, SSH key, and environments.yaml

You’ll need an API key from MAAS so that the Juju client can access it. Each user account in MAAS can have as many API keys as desired. One hard and fast rule is that you’ll need to use a different API key for each Juju environment you set up within a single MAAS cluster.

You’ll also need to add an SSH key to MAAS so that you, and Juju, can SSH into freshly provisioned machines.

Getting a key

To get the API key:

1. Go to your MAAS preferences page, or go to your MAAS home page and choose Preferences from the drop-down menu that appears when clicking your username at the top-right of the page.
2. Optionally add a new MAAS key. Do this if you’re setting up another environment within the same MAAS cluster.

Adding an SSH key

While you’re still on the MAAS preferences page, add your SSH key by clicking Add SSH key. Use the public half of your SSH key, the content of ~/.ssh/id_rsa.pub for example; don’t paste the private half.

Creating environments.yaml

Create or modify ~/.juju/environments.yaml with the following content:

juju: environments
environments:
  maas:
    type: maas
    maas-server: 'http://localhost:5240'
    maas-oauth: '${maas-api-key}'
    admin-secret: 'nothing'

Substitute the API key from earlier into the ${maas-api-key} slot. You may need to modify the maas-server setting too; if you’re running from the maas package it should be something like http://hostname.example.com/MAAS.

Now Juju

$ juju status

Note: if Juju complains that there are multiple environments and no explicit default, add -e ${environment-name} after each command, e.g.:

$ juju status -e maas

As you’ve not bootstrapped you ought to see:

juju environment not found: is the environment bootstrapped?

Bootstrap:

$ juju bootstrap

This will return quickly, but the master node may take a long time to come up. It has to completely install Ubuntu and Zookeeper and reboot before it’ll be available for use. It’s probably worth either trying a juju status once in a while to check on progress, or following the install on the node directly.

Beware of bug 413415 - console-setup hangs under chroot debootstrap with a console login on ttyX - when monitoring an installation on the node.

If you’re using vdenv (included in lp:maas) then virsh makes it easy to follow on progress:

$ virsh list
 Id Name                 State
----------------------------------
  1 zimmer               running
  2 odev-node02          running

$ gnome-terminal -e 'virsh console odev-node02' &

zimmer is the machine on which the MAAS server is running. Here odev-node02 is the machine being bootstrapped as the Juju master node.

Once the master node has been installed a status command should come up with something a bit more interesting:

machines:
  0:
    agent-state: running
    dns-name: odev-node02
    instance-id: /api/1.0/nodes/odev-node02/
    instance-state: unknown
services: {}

Now it’s possible to deploy a charm:

$ juju deploy --repository /usr/share/doc/juju/examples local:oneiric/mysql
$ juju status

If you have another node free you can finish off the canonical and by now familiar example:

$ juju deploy --repository /usr/share/doc/juju/examples local:oneiric/wordpress
$ juju add-relation wordpress mysql
$ juju expose wordpress
$ juju status

Note that each charm runs on its own host, so each deployment will actually take as long as it took to bootstrap. Have a beer, drown your sorrows in liquor, or, my preference, have another cup of tea.

---