README.md

DevStack is a set of scripts and utilities to quickly deploy an OpenStack cloud.

# Goals

* To quickly build dev OpenStack environments in a clean Ubuntu or Fedora
  environment
* To describe working configurations of OpenStack (which code branches
  work together?  what do config files look like for those branches?)
* To make it easier for developers to dive into OpenStack so that they can
  productively contribute without having to understand every part of the
  system at once
* To make it easy to prototype cross-project features
* To provide an environment for the OpenStack CI testing on every commit
  to the projects

Read more at http://devstack.org.

IMPORTANT: Be sure to carefully read `stack.sh` and any other scripts you
execute before you run them, as they install software and will alter your
networking configuration.  We strongly recommend that you run `stack.sh`
in a clean and disposable vm when you are first getting started.

# Versions

The DevStack master branch generally points to trunk versions of OpenStack
components.  For older, stable versions, look for branches named
stable/[release] in the DevStack repo.  For example, you can do the
following to create a juno OpenStack cloud:

    git checkout stable/juno
    ./stack.sh

You can also pick specific OpenStack project releases by setting the appropriate
`*_BRANCH` variables in the ``localrc`` section of `local.conf` (look in
`stackrc` for the default set).  Usually just before a release there will be
milestone-proposed branches that need to be tested::

    GLANCE_REPO=git://git.openstack.org/openstack/glance.git
    GLANCE_BRANCH=milestone-proposed

# Start A Dev Cloud

Installing in a dedicated disposable VM is safer than installing on your
dev machine!  Plus you can pick one of the supported Linux distros for
your VM.  To start a dev cloud run the following NOT AS ROOT (see
**DevStack Execution Environment** below for more on user accounts):

    ./stack.sh

When the script finishes executing, you should be able to access OpenStack
endpoints, like so:

* Horizon: http://myhost/
* Keystone: http://myhost:5000/v2.0/

We also provide an environment file that you can use to interact with your
cloud via CLI:

    # source openrc file to load your environment with OpenStack CLI creds
    . openrc
    # list instances
    nova list

If the EC2 API is your cup-o-tea, you can create credentials and use euca2ools:

    # source eucarc to generate EC2 credentials and set up the environment
    . eucarc
    # list instances using ec2 api
    euca-describe-instances

# DevStack Execution Environment

DevStack runs rampant over the system it runs on, installing things and
uninstalling other things.  Running this on a system you care about is a recipe
for disappointment, or worse.  Alas, we're all in the virtualization business
here, so run it in a VM.  And take advantage of the snapshot capabilities
of your hypervisor of choice to reduce testing cycle times.  You might even save
enough time to write one more feature before the next feature freeze...

``stack.sh`` needs to have root access for a lot of tasks, but uses ``sudo``
for all of those tasks.  However, it needs to be not-root for most of its
work and for all of the OpenStack services.  ``stack.sh`` specifically
does not run if started as root.

This is a recent change (Oct 2013) from the previous behaviour of
automatically creating a ``stack`` user.  Automatically creating
user accounts is not the right response to running as root, so
that bit is now an explicit step using ``tools/create-stack-user.sh``.
Run that (as root!) or just check it out to see what DevStack's
expectations are for the account it runs under.  Many people simply
use their usual login (the default 'ubuntu' login on a UEC image
for example).

# Customizing

You can override environment variables used in `stack.sh` by creating
file name `local.conf` with a ``localrc`` section as shown below.  It
is likely that you will need to do this to tweak several settings for
your environment.

    [[local|localrc]]
    VARIABLE=value

Start by reading the [configuration
guide](doc/source/configuration.rst) for details of the many available
options.