Juju Digital Ocean Provider

This package provides a cli plugin for juju that allows for automated provisioning of machines on digital ocean. I like to call it JuDo :-)

Digital ocean is linux vps provider utilizing kvm and ssd across multiple data centers at a very competitive price with hourly billing.

Juju provides for workloads management and orchestration using a collection of workloads definitions (charms) that can be assembled lego fashion at runtime into complex application topologies.

You can find out more about juju at its home page. http://juju.ubuntu.com

Install

This plugin requires a version of juju >= 1.18.0

A usable version of juju is available out of the box in ubuntu 14.04 and later versions. For earlier versions of ubuntu, please use the stable ppa:

$ sudo add-apt-repository ppa:juju/stable
$ apt-get update && apt-get install juju
$ juju version
1.20.4-precise-amd64

Plugin installation is done via pip/easy_install which is the python language package managers, its available by default on ubuntu. Also recommended is virtualenv to sandbox this install from your system packages:

$ pip install -U juju-docean

Fwiw, currently the transitive dependency tree is PyYAML, requests, dop.

Setup

There are three steps for configuration and setup of this provider. Configuring your digital ocean api keys, adding an environment to juju's config file, and setting up an ssh key for usage on digital ocean machines.

DO API Keys

A digital ocean account is a pre-requisite, If you don't have a digital ocean account you can sign up here.

Credentials for the digital ocean api can be obtained from your account dashboard at https://cloud.digitalocean.com/settings/applications

The credentials can be provided to the plugin via:

• Environment variable DO_OAUTH_TOKEN

If you're using an older version of juju-docean, it still accepts the digitalocean api v1 credentials via:

• Environment variables DO_CLIENT_ID and DO_API_KEY

This digital ocean plugin uses the manual provisioning capabilities of juju core. As a result its required to allocate machines in the environment before deploying workloads. We'll explore that more in a moment.

SSH Key

An ssh key is required for use by this plugin and the public key must be uploaded to the digital ocean control panel. By default all keys in the digital ocean account will be tried, so no user configuration is needed. A specific key to utilize can be specified with the environment variable DO_SSH_KEY="key_name" where key_name is the name of the key in the digital ocean management console.

Juju Config

Next let's configure a juju environment for digital ocean, add a manual provider environment to 'environments.yaml', for example:

environments:
  digitalocean:
     type: manual
     bootstrap-host: null
     bootstrap-user: root

Usage

We need to tell juju which environment we want to use, there are several ways to do this, either of the following will do the trick:

$ juju switch digitalocean
$ export JUJU_ENV=digitalocean

Now we can bootstrap our digital ocean environment:

$ juju docean bootstrap --constraints="mem=2g, region=nyc1"

Which will create a droplet with 2Gb of ram in the nyc1 data center.

All machines created by this plugin will have the juju environment name as a prefix for their droplet name if your looking at the DO control panel.

After our environment is bootstrapped we can add additional machines to it via the the add-machine command, for example the following will add 2 additional machines with 2Gb each:

$ juju docean add-machine -n 2 --constraints="mem=2G, region=nyc2"
$ juju status

environment: docean
machines:
  "0":
    agent-state: started
    agent-version: 1.17.2.1
    dns-name: 162.243.115.78
    instance-id: 'manual:'
    series: precise
    hardware: arch=amd64 cpu-cores=1 mem=2002M
  "1":
    agent-state: started
    agent-version: 1.17.2.1
    dns-name: 162.243.86.238
    instance-id: manual:162.243.86.238
    series: precise
    hardware: arch=amd64 cpu-cores=1 mem=2002M
  "2":
    agent-state: started
    agent-version: 1.17.2.1
    dns-name: 107.170.39.10
    instance-id: manual:107.170.39.10
    series: precise
    hardware: arch=amd64 cpu-cores=1 mem=2002M
services: {}

We can now use standard juju commands for deploying service workloads aka charms:

$ juju deploy wordpress

Without specifying the machine to place the workload on, the machine will automatically go to an unused machine within the environment.

There are hundreds of available charms ready to be used, you can find out more about what's out there from http://jujucharms.com Or alternatively the 'plain' html version at http://manage.jujucharms.com/charms/precise

We can use manual placement to deploy target particular machines:

$ juju deploy mysql --to=2

And of course the real magic of juju comes in its ability to assemble these workloads together via relations like lego blocks:

$ juju add-relation wordpress mysql

We can list all machines in digitalocean that are part of the juju environment with the list-machines command. This directly queries the digital ocean api and does not interact with juju api. It also takes a --all option to list all machines in digitalocean account (irrespective of environment).:

$ juju docean list-machines

Id       Name               Size  Status   Created      Region Address
2442349  ocean-0            512MB active   2014-08-25   nyc2   162.243.123.121
2442360  ocean-ef19ad5cc... 512MB active   2014-08-25   nyc2   162.243.51.21
2442361  ocean-145bf7a80... 512MB active   2014-08-25   nyc2   104.131.201.155
2442402  ocean-a9678a03e... 2GB   active   2014-08-25   nyc3   104.131.43.243
2442403  ocean-f35ffedd9... 2GB   active   2014-08-25   nyc3   104.131.43.242

We can terminate allocated machines by their machine id. By default with the docean plugin, machines are forcibly terminated which will also terminate any service units on those machines:

$ juju docean terminate-machine 1 2

And we can destroy the entire environment via:

$ juju docean destroy-environment

destroy-environment also takes a --force option which only uses the digital ocean api. Its helpful if state server or other machines are killed independently of juju.

All commands have builtin help facilities and accept a -v option which will print verbose output while running.

You can find out more about using from http://juju.ubuntu.com/docs

Constraints

Constraints are selection criteria used to determine what type of machine to allocate for an environment. Those criteria can be related to size of the machine, its location, or other provider specific criteria.

This plugin accepts the standard juju constraints

• cpu-cores
• memory
• root-disk

Additionally it supports the following provider specific constraints.

• 'region' to denote the digital ocean data center to utilize. All digitalocean data centers are supported and various short hand aliases are defined. ie. valid values include ams2, nyc1, nyc2, sfo1, sg1. The plugin defaults to nyc3.
• 'transfer' to denote the terabytes of transfer included in the instance montly cost (integer size in terabytes).

Contributing

Bug reports and pull requests welcome.

Contributors

• Kapil Thangavelu - Maintainer
• Bruce Frederiksen - DO v2 Support