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 grizzly OpenStack cloud:

     git checkout stable/grizzly

     ./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 your networking configuration should
 you need to access your cloud from a different host.
 
     [[local|localrc]]
     VARIABLE=value
 
 See the **Local Configuration** section below for more details.

 # Database Backend
 
 Multiple database backends are available. The available databases are defined in the lib/databases directory.

 `mysql` is the default database, choose a different one by putting the
 following in the `localrc` section:

     disable_service mysql
     enable_service postgresql

 `mysql` is the default database.

 # RPC Backend
 
 Multiple RPC backends are available. Currently, this
 includes RabbitMQ (default), Qpid, and ZeroMQ. Your backend of

 choice may be selected via the `localrc` section.

 
 Note that selecting more than one RPC backend will result in a failure.
 
 Example (ZeroMQ):
 
     ENABLED_SERVICES="$ENABLED_SERVICES,-rabbit,-qpid,zeromq"
 
 Example (Qpid):
 
     ENABLED_SERVICES="$ENABLED_SERVICES,-rabbit,-zeromq,qpid"
 

 # Apache Frontend
 

 Apache web server is enabled for wsgi services by setting
 `APACHE_ENABLED_SERVICES` in your ``localrc`` section.  Remember to
 enable these services at first as above.

 
     APACHE_ENABLED_SERVICES+=keystone,swift
 

 # Swift
 

 Swift is disabled by default.  When enabled, it is configured with
 only one replica to avoid being IO/memory intensive on a small
 vm. When running with only one replica the account, container and
 object services will run directly in screen. The others services like
 replicator, updaters or auditor runs in background.

 If you would like to enable Swift you can add this to your `localrc` section:

     enable_service s-proxy s-object s-container s-account

 If you want a minimal Swift install with only Swift and Keystone you

 can have this instead in your `localrc` section:

     disable_all_services

     enable_service key mysql s-proxy s-object s-container s-account
 

 If you only want to do some testing of a real normal swift cluster
 with multiple replicas you can do so by customizing the variable

 `SWIFT_REPLICAS` in your `localrc` section (usually to 3).

 # Swift S3

 If you are enabling `swift3` in `ENABLED_SERVICES` DevStack will

 install the swift3 middleware emulation. Swift will be configured to
 act as a S3 endpoint for Keystone so effectively replacing the
 `nova-objectstore`.

 Only Swift proxy server is launched in the screen session all other
 services are started in background and managed by `swift-init` tool.

 # Neutron

 
 Basic Setup
 

 In order to enable Neutron a single node setup, you'll need the

 following settings in your `local.conf`:

 
     disable_service n-net
     enable_service q-svc
     enable_service q-agt
     enable_service q-dhcp
     enable_service q-l3
     enable_service q-meta

     enable_service q-metering

     # Optional, to enable tempest configuration as part of DevStack

     enable_service tempest
 

 Then run `stack.sh` as normal.
 

 DevStack supports setting specific Neutron configuration flags to the
 service, Open vSwitch plugin and LinuxBridge plugin configuration files.

 To make use of this feature, the settings can be added to ``local.conf``.
 The old ``Q_XXX_EXTRA_XXX_OPTS`` variables are deprecated and will be removed
 in the near future.  The ``local.conf`` headers for the replacements are:

 * ``Q_SRV_EXTRA_OPTS``:
 
     [[post-config|/$Q_PLUGIN_CONF_FILE]]
     [linuxbridge]   # or [ovs]
 
 * ``Q_AGENT_EXTRA_AGENT_OPTS``:
 
     [[post-config|/$Q_PLUGIN_CONF_FILE]]
     [agent]
 
 * ``Q_AGENT_EXTRA_SRV_OPTS``:
 
     [[post-config|/$Q_PLUGIN_CONF_FILE]]
     [linuxbridge]   # or [ovs]
 
 * ``Q_SRV_EXTRA_DEFAULT_OPTS``:
 
     [[post-config|$NEUTRON_CONF]]
     [DEFAULT]
 
 Example extra config in `local.conf`:

     [[post-config|/$Q_PLUGIN_CONF_FILE]]
     [agent]
     tunnel_type=vxlan
     vxlan_udp_port=8472

     [[post-config|$NEUTRON_CONF]]
     [DEFAULT]
     tenant_network_type=vxlan

 DevStack also supports configuring the Neutron ML2 plugin. The ML2 plugin

 can run with the OVS, LinuxBridge, or Hyper-V agents on compute hosts. This
 is a simple way to configure the ml2 plugin:

 
     # VLAN configuration
     Q_PLUGIN=ml2
     ENABLE_TENANT_VLANS=True
 
     # GRE tunnel configuration
     Q_PLUGIN=ml2
     ENABLE_TENANT_TUNNELS=True
 
     # VXLAN tunnel configuration
     Q_PLUGIN=ml2
     Q_ML2_TENANT_NETWORK_TYPE=vxlan
 

 The above will default in DevStack to using the OVS on each compute host.
 To change this, set the `Q_AGENT` variable to the agent you want to run
 (e.g. linuxbridge).

 
     Variable Name                    Notes
     -------------------------------------------------------------------------------------
     Q_AGENT                          This specifies which agent to run with the ML2 Plugin (either `openvswitch` or `linuxbridge`).
     Q_ML2_PLUGIN_MECHANISM_DRIVERS   The ML2 MechanismDrivers to load. The default is none. Note, ML2 will work with the OVS and LinuxBridge agents by default.
     Q_ML2_PLUGIN_TYPE_DRIVERS        The ML2 TypeDrivers to load. Defaults to all available TypeDrivers.
     Q_ML2_PLUGIN_GRE_TYPE_OPTIONS    GRE TypeDriver options. Defaults to none.
     Q_ML2_PLUGIN_VXLAN_TYPE_OPTIONS  VXLAN TypeDriver options. Defaults to none.
     Q_ML2_PLUGIN_VLAN_TYPE_OPTIONS   VLAN TypeDriver options. Defaults to none.
 

 # Heat
 
 Heat is disabled by default. To enable it you'll need the following settings

 in your `localrc` section:

 
     enable_service heat h-api h-api-cfn h-api-cw h-eng
 
 Heat can also run in standalone mode, and be configured to orchestrate
 on an external OpenStack cloud. To launch only Heat in standalone mode

 you'll need the following settings in your `localrc` section:

 
     disable_all_services
     enable_service rabbit mysql heat h-api h-api-cfn h-api-cw h-eng
     HEAT_STANDALONE=True
     KEYSTONE_SERVICE_HOST=...
     KEYSTONE_AUTH_HOST=...
 

 # Tempest

 
 If tempest has been successfully configured, a basic set of smoke tests can be run as follows:
 
     $ cd /opt/stack/tempest

     $ tox -efull  tempest.scenario.test_network_basic_ops

 # DevStack on Xenserver
 
 If you would like to use Xenserver as the hypervisor, please refer to the instructions in `./tools/xen/README.md`.
 

 # Additional Projects
 

 DevStack has a hook mechanism to call out to a dispatch script at specific
 points in the execution of `stack.sh`, `unstack.sh` and `clean.sh`.  This
 allows upper-layer projects, especially those that the lower layer projects
 have no dependency on, to be added to DevStack without modifying the core
 scripts.  Tempest is built this way as an example of how to structure the
 dispatch script, see `extras.d/80-tempest.sh`.  See `extras.d/README.md`
 for more information.

 # Multi-Node Setup

 A more interesting setup involves running multiple compute nodes, with Neutron networks connecting VMs on different compute nodes.

 You should run at least one "controller node", which should have a `stackrc` that includes at least:
 
     disable_service n-net
     enable_service q-svc
     enable_service q-agt
     enable_service q-dhcp
     enable_service q-l3
     enable_service q-meta

     enable_service neutron

 You likely want to change your `localrc` section to run a scheduler that
 will balance VMs across hosts:

 
     SCHEDULER=nova.scheduler.simple.SimpleScheduler
 
 You can then run many compute nodes, each of which should have a `stackrc` which includes the following, with the IP address of the above controller node:
 

     ENABLED_SERVICES=n-cpu,rabbit,g-api,neutron,q-agt

     SERVICE_HOST=[IP of controller node]
     MYSQL_HOST=$SERVICE_HOST
     RABBIT_HOST=$SERVICE_HOST
     Q_HOST=$SERVICE_HOST

     MATCHMAKER_REDIS_HOST=$SERVICE_HOST

 
 # Cells
 
 Cells is a new scaling option with a full spec at http://wiki.openstack.org/blueprint-nova-compute-cells.
 

 To setup a cells environment add the following to your `localrc` section:

 
     enable_service n-cell

 
 Be aware that there are some features currently missing in cells, one notable one being security groups.  The exercises have been patched to disable functionality not supported by cells.

 
 
 # Local Configuration
 
 Historically DevStack has used ``localrc`` to contain all local configuration and customizations. More and more of the configuration variables available for DevStack are passed-through to the individual project configuration files.  The old mechanism for this required specific code for each file and did not scale well.  This is handled now by a master local configuration file.
 
 # local.conf
 
 The new config file ``local.conf`` is an extended-INI format that introduces a new meta-section header that provides some additional information such as a phase name and destination config filename:
 

     [[ <phase> | <config-file-name> ]]

 where ``<phase>`` is one of a set of phase names defined by ``stack.sh``
 and ``<config-file-name>`` is the configuration filename.  The filename is
 eval'ed in the ``stack.sh`` context so all environment variables are
 available and may be used.  Using the project config file variables in
 the header is strongly suggested (see the ``NOVA_CONF`` example below).
 If the path of the config file does not exist it is skipped.

 
 The defined phases are:
 

 * **local** - extracts ``localrc`` from ``local.conf`` before ``stackrc`` is sourced
 * **post-config** - runs after the layer 2 services are configured and before they are started
 * **extra** - runs after services are started and before any files in ``extra.d`` are executed

 * **post-extra** - runs after files in ``extra.d`` are executed

 
 The file is processed strictly in sequence; meta-sections may be specified more than once but if any settings are duplicated the last to appear in the file will be used.
 

     [[post-config|$NOVA_CONF]]
     [DEFAULT]
     use_syslog = True

     [osapi_v3]
     enabled = False

 A specific meta-section ``local|localrc`` is used to provide a default
 ``localrc`` file (actually ``.localrc.auto``).  This allows all custom
 settings for DevStack to be contained in a single file.  If ``localrc``
 exists it will be used instead to preserve backward-compatibility.

     [[local|localrc]]
     FIXED_RANGE=10.254.1.0/24
     ADMIN_PASSWORD=speciale
     LOGFILE=$DEST/logs/stack.sh.log

 Note that ``Q_PLUGIN_CONF_FILE`` is unique in that it is assumed to *NOT*
 start with a ``/`` (slash) character.  A slash will need to be added:

     [[post-config|/$Q_PLUGIN_CONF_FILE]]