Devstack

DevStack is a set of scripts and utilities to quickly deploy an OpenStack cloud from git source trees.

Goals

• To quickly build dev OpenStack environments in a clean Ubuntu or RockyLinux 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 https://docs.openstack.org/devstack/latest

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 Zed OpenStack cloud:

git checkout stable/zed
./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=https://opendev.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/identity/v3/

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
openstack server list

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.

DevStack will not automatically create the user, but provides a helper script in 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

DevStack can be extensively configured via the configuration file local.conf. It is likely that you will need to provide and modify this file if you want anything other than the most basic setup. Start by reading the configuration guide for details of the configuration file and the many available options.