devstack/doc/source/faq.rst

FAQ

General Questions

Can I use DevStack for production?

DevStack is targeted at developers and CI systems to use the raw upstream code. It makes many choices that are not appropriate for production systems.

Your best choice is probably to choose a distribution of OpenStack.

Why a shell script, why not chef/puppet/...

The script is meant to be read by humans (as well as ran by computers); it is the primary documentation after all. Using a recipe system requires everyone to agree and understand chef or puppet.

I'd like to help!

That isn't a question, but please do! The source for DevStack is at git.openstack.org and bug reports go to LaunchPad. Contributions follow the usual process as described in the developer guide. This Sphinx documentation is housed in the doc directory.

Why not use packages?

Unlike packages, DevStack leaves your cloud ready to develop -checkouts of the code and services running in screen. However, many people are doing the hard work of packaging and recipes for production deployments.

Why isn't $MY_FAVORITE_DISTRO supported?

DevStack is meant for developers and those who want to see how OpenStack really works. DevStack is known to run on the distro/release combinations listed in README.md. DevStack is only supported on releases other than those documented in README.md on a best-effort basis.

Are there any differences between Ubuntu and Centos/Fedora support?

Both should work well and are tested by DevStack CI.

Why can't I use another shell?

DevStack now uses some specific bash-ism that require Bash 4, such as associative arrays. Simple compatibility patches have been accepted in the past when they are not complex, at this point no additional compatibility patches will be considered except for shells matching the array functionality as it is very ingrained in the repo and project management.

Can I test on OS/X?

Some people have success with bash 4 installed via homebrew to keep running tests on OS/X.

Operation and Configuration

Can DevStack handle a multi-node installation?

Yes, see multinode lab guide <guides/multinode-lab>

How can I document the environment that DevStack is using?

DevStack includes a script (tools/info.sh) that gathers the versions of the relevant installed apt packages, pip packages and git repos. This is a good way to verify what Python modules are installed.

How do I turn off a service that is enabled by default?

Services can be turned off by adding disable_service xxx to local.conf (using n-vol in this example):

disable_service n-vol

Is enabling a service that defaults to off done with the reverse of the above?

Of course!

enable_service qpid

How do I run a specific OpenStack milestone?

OpenStack milestones have tags set in the git repo. Set the appropriate tag in the *_BRANCH variables in local.conf. Swift is on its own release schedule so pick a tag in the Swift repo that is just before the milestone release. For example:

[[local|localrc]]
GLANCE_BRANCH=stable/kilo
HORIZON_BRANCH=stable/kilo
KEYSTONE_BRANCH=stable/kilo
NOVA_BRANCH=stable/kilo
GLANCE_BRANCH=stable/kilo
NEUTRON_BRANCH=stable/kilo
SWIFT_BRANCH=2.3.0

What can I do about RabbitMQ not wanting to start on my fresh new VM?

This is often caused by erlang not being happy with the hostname resolving to a reachable IP address. Make sure your hostname resolves to a working IP address; setting it to 127.0.0.1 in /etc/hosts is often good enough for a single-node installation. And in an extreme case, use clean.sh to eradicate it and try again.

Configure local.conf thusly:

[[local|localrc]]
HEAT_STANDALONE=True
ENABLED_SERVICES=rabbit,mysql,heat,h-api,h-api-cfn,h-api-cw,h-eng
KEYSTONE_SERVICE_HOST=<keystone-host>
KEYSTONE_AUTH_HOST=<keystone-host>

Why are my configuration changes ignored?

You may have run into the package prerequisite installation timeout. tools/install_prereqs.sh has a timer that skips the package installation checks if it was run within the last PREREQ_RERUN_HOURS hours (default is 2). To override this, set FORCE_PREREQ=1 and the package checks will never be skipped.

Miscellaneous

tools/fixup_stuff.sh is broken and shouldn't 'fix' just one version of packages.

Stuff in there is to correct problems in an environment that need to be fixed elsewhere or may/will be fixed in a future release. In the case of httplib2 and prettytable specific problems with specific versions are being worked around. If later releases have those problems than we'll add them to the script. Knowing about the broken future releases is valuable rather than polling to see if it has been fixed.