Digital Ocean integration with juju
This package provides a cli plugin for juju that allows for cli based provisioning of machines on digital ocean.
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.
This plugin requires a development version of juju (> 1.17.2)
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
Currently the transitive dependency tree is PyYAML, requests, dop.
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/api_access
The credentials can be provided to the plugin via one three ways.
- Environment variables DO_CLIENT_ID and DO_API_KEY
- Command line parameters
- A config file
The config file must be placed in the JUJU_HOME directory (default ~/.juju) and must be named docean.conf. This file is in ini format. Sample contents below:
DO_CLIENT_ID = aoweirj DO_API_KEY = asdfo DO_SSH_KEY = default
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.
An ssh key is required for use by this plugin and the public key must be uploaded to the digital ocean control panel. If you have multiple keys there you can specify the key name to use when creating instances via the environment variable DO_SSH_KEY, config file, or cli parameter.
Note If you have a large number of ssh keys, ssh will only attempt a certain number of key logins before giving up, ideally you want to use one the keys it will select first. Its not possible at this moment to specify a private key to use for ssh. (see http://pad.lv/1270466)
Next let’s configure a juju environment for digital ocean, add an a null provider enviroment to ‘environments.yaml’, for example:
environments: digitalocean: type: manual bootstrap-host: null bootstrap-user: root
Now we can bootstrap an environment:
$ juju docean bootstrap --constraints="mem=512Mb, region=ams"
All machines created by this plugin will have the juju environment name as a prefix for their droplet name.
After our environment is bootstrapped we can add additional machines to it via the the add-machine command, for example the following will add 5 machines with 2Gb each:
$ juju docean add-machine -n 5 --constraints="mem=2G"
We can now use standard juju commands for deploying workloads:
$ juju deploy wordpress $ juju deploy mysql $ juju add-relation wordpress mysql $ juju status
We can terminate allocated machines by their machine id.
$ juju docean terminate-machine 1 2 3
Machines can also be forcibly terminated, which will also terminate any units on those machines, and is not dependent on the machine actually running.
$ juju docean terminate-machine --force 5
And we can destroy the entire environment via:
$ juju docean destroy-environment
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
Additionally it supports the following provider specific constraints.
- ‘region’ to denote the data center to utilize (currently ‘ams2’, ‘nyc1’, ‘nyc2’) defaulting to ‘nyc2’.
- ‘transfer’ to denote the terabytes of transfer included in the instance montly cost.