devstack/doc/source/configuration.rst

=============
Configuration
=============

.. contents::
   :local:
   :depth: 1

DevStack has always tried to be mostly-functional with a minimal amount
of configuration. The number of options has ballooned as projects add
features, new projects added and more combinations need to be tested.
Historically DevStack obtained all local configuration and
customizations from a ``localrc`` file. The number of configuration
variables that are simply passed-through to the individual project
configuration files is also increasing. The old mechanism for this
(``EXTRAS_OPTS`` and friends) required specific code for each file and
did not scale well.

In Oct 2013 a new configuration method was introduced (in `review
46768 <https://review.openstack.org/#/c/46768/>`__) to hopefully
simplify this process and meet the following goals:

-  contain all non-default local configuration in a single file
-  be backward-compatible with ``localrc`` to smooth the transition
   process
-  allow settings in arbitrary configuration files to be changed

local.conf
==========

The new configuration file is ``local.conf`` and should reside in the
root Devstack directory. An example of such ``local.conf`` file
is provided in the ``devstack/samples`` directory. Copy this file into
the root Devstack directory and adapt it to your needs. It is a modified INI
format file that introduces a meta-section header to carry additional
information regarding the configuration files to be changed.

The new header is similar to a normal INI section header but with double
brackets (``[[ ... ]]``) and two internal fields separated by a pipe
(``|``):

::

    [[ <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
-  **pre-install** - runs after the system packages are installed but
   before any of the source repositories are installed
-  **install** - runs immediately after the repo installations are
   complete
-  **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

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. More
details on the :doc:`contents of local.conf <local.conf>` are available.

::

    [[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]]

Also note that the ``localrc`` section is sourced as a shell script
fragment and MUST conform to the shell requirements, specifically no
whitespace around ``=`` (equals).

.. _minimal-configuration:

Minimal Configuration
=====================

While ``stack.sh`` is happy to run without a ``localrc`` section in
``local.conf``, devlife is better when there are a few minimal variables
set. This is an example of a minimal configuration that touches the
values that most often need to be set.

-  no logging
-  pre-set the passwords to prevent interactive prompts
-  move network ranges away from the local network (``FIXED_RANGE`` and
   ``FLOATING_RANGE``, commented out below)
-  set the host IP if detection is unreliable (``HOST_IP``, commented
   out below)

::

    [[local|localrc]]
    ADMIN_PASSWORD=secrete
    DATABASE_PASSWORD=$ADMIN_PASSWORD
    RABBIT_PASSWORD=$ADMIN_PASSWORD
    SERVICE_PASSWORD=$ADMIN_PASSWORD
    SERVICE_TOKEN=a682f596-76f3-11e3-b3b2-e716f9080d50
    #FIXED_RANGE=172.31.1.0/24
    #FLOATING_RANGE=192.168.20.0/25
    #HOST_IP=10.3.4.5

If the ``*_PASSWORD`` variables are not set here you will be prompted to
enter values for them by ``stack.sh``.

The network ranges must not overlap with any networks in use on the
host. Overlap is not uncommon as RFC-1918 'private' ranges are commonly
used for both the local networking and Nova's fixed and floating ranges.

``HOST_IP`` is normally detected on the first run of ``stack.sh`` but
often is indeterminate on later runs due to the IP being moved from an
Ethernet interface to a bridge on the host. Setting it here also makes it
available for ``openrc`` to set ``OS_AUTH_URL``. ``HOST_IP`` is not set
by default.

``HOST_IPV6`` is normally detected on the first run of ``stack.sh`` but
will not be set if there is no IPv6 address on the default Ethernet interface.
Setting it here also makes it available for ``openrc`` to set ``OS_AUTH_URL``.
``HOST_IPV6`` is not set by default.

Configuration Notes
===================

.. contents::
   :local:

Installation Directory
----------------------

The DevStack install directory is set by the ``DEST`` variable.  By
default it is ``/opt/stack``.

By setting it early in the ``localrc`` section you can reference it in
later variables.  It can be useful to set it even though it is not
changed from the default value.

    ::

        DEST=/opt/stack

Logging
-------

Enable Logging
~~~~~~~~~~~~~~

By default ``stack.sh`` output is only written to the console where it
runs. It can be sent to a file in addition to the console by setting
``LOGFILE`` to the fully-qualified name of the destination log file. A
timestamp will be appended to the given filename for each run of
``stack.sh``.

    ::

        LOGFILE=$DEST/logs/stack.sh.log

Old log files are cleaned automatically if ``LOGDAYS`` is set to the
number of days of old log files to keep.

    ::

        LOGDAYS=1

The some of the project logs (Nova, Cinder, etc) will be colorized by
default (if ``SYSLOG`` is not set below); this can be turned off by
setting ``LOG_COLOR`` to ``False``.

    ::

        LOG_COLOR=False

Logging the Service Output
~~~~~~~~~~~~~~~~~~~~~~~~~~

DevStack will log the ``stdout`` output of the services it starts.
When using ``screen`` this logs the output in the screen windows to a
file.  Without ``screen`` this simply redirects stdout of the service
process to a file in ``LOGDIR``.

    ::

        LOGDIR=$DEST/logs

*Note the use of ``DEST`` to locate the main install directory; this
is why we suggest setting it in ``local.conf``.*

Enabling Syslog
~~~~~~~~~~~~~~~

Logging all services to a single syslog can be convenient. Enable
syslogging by setting ``SYSLOG`` to ``True``. If the destination log
host is not localhost ``SYSLOG_HOST`` and ``SYSLOG_PORT`` can be used
to direct the message stream to the log host.  |

    ::

        SYSLOG=True
        SYSLOG_HOST=$HOST_IP
        SYSLOG_PORT=516

Libraries from Git
------------------

By default devstack installs OpenStack server components from git,
however it installs client libraries from released versions on pypi.
This is appropriate if you are working on server development, but if
you want to see how an unreleased version of the client affects the
system you can have devstack install it from upstream, or from local
git trees by specifying it in ``LIBS_FROM_GIT``.  Multiple libraries
can be specified as a comma separated list.

   ::

      LIBS_FROM_GIT=python-keystoneclient,oslo.config

Virtual Environments
--------------------

Enable the use of Python virtual environments by setting ``USE_VENV``
to ``True``.  This will enable the creation of venvs for each project
that is defined in the ``PROJECT_VENV`` array.

Each entry in the ``PROJECT_VENV`` array contains the directory name
of a venv to be used for the project.  The array index is the project
name.  Multiple projects can use the same venv if desired.

  ::

    PROJECT_VENV["glance"]=${GLANCE_DIR}.venv

``ADDITIONAL_VENV_PACKAGES`` is a comma-separated list of additional
packages to be installed into each venv.  Often projects will not have
certain packages listed in its ``requirements.txt`` file because they
are 'optional' requirements, i.e. only needed for certain
configurations.  By default, the enabled databases will have their
Python bindings added when they are enabled.

  ::

     ADDITIONAL_VENV_PACKAGES="python-foo, python-bar"


A clean install every time
--------------------------

By default ``stack.sh`` only clones the project repos if they do not
exist in ``$DEST``. ``stack.sh`` will freshen each repo on each run if
``RECLONE`` is set to ``yes``. This avoids having to manually remove
repos in order to get the current branch from ``$GIT_BASE``.

    ::

        RECLONE=yes

Upgrade packages installed by pip
---------------------------------

By default ``stack.sh`` only installs Python packages if no version is
currently installed or the current version does not match a specified
requirement. If ``PIP_UPGRADE`` is set to ``True`` then existing
required Python packages will be upgraded to the most recent version
that matches requirements.

    ::

        PIP_UPGRADE=True

Swift
-----

Swift is now used as the back-end for the S3-like object store.  When
enabled Nova's objectstore (``n-obj`` in ``ENABLED_SERVICES``) is
automatically disabled. Enable Swift by adding it services to
``ENABLED_SERVICES``

    ::

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

Setting Swift's hash value is required and you will be prompted for it
if Swift is enabled so just set it to something already:

    ::

        SWIFT_HASH=66a3d6b56c1f479c8b4e70ab5c2000f5

For development purposes the default number of replicas is set to
``1`` to reduce the overhead required. To better simulate a production
deployment set this to ``3`` or more.

    ::

        SWIFT_REPLICAS=3

The data for Swift is stored in the source tree by default (in
``$DEST/swift/data``) and can be moved by setting
``SWIFT_DATA_DIR``. The specified directory will be created if it does
not exist.

    ::

        SWIFT_DATA_DIR=$DEST/data/swift

*Note*: Previously just enabling ``swift`` was sufficient to start the
Swift services. That does not provide proper service granularity,
particularly in multi-host configurations, and is considered
deprecated. Some service combination tests now check for specific
Swift services and the old blanket acceptance will longer work
correctly.

Service Catalog Backend
-----------------------

By default DevStack uses Keystone's ``sql`` service catalog backend.
An alternate ``template`` backend is also available, however, it does
not support the ``service-*`` and ``endpoint-*`` commands of the
``keystone`` CLI.  To do so requires the ``sql`` backend be enabled
with ``KEYSTONE_CATALOG_BACKEND``:

    ::

        KEYSTONE_CATALOG_BACKEND=template

DevStack's default configuration in ``sql`` mode is set in
``files/keystone_data.sh``

Cinder
------

The logical volume group used to hold the Cinder-managed volumes is
set by ``VOLUME_GROUP``, the logical volume name prefix is set with
``VOLUME_NAME_PREFIX`` and the size of the volume backing file is set
with ``VOLUME_BACKING_FILE_SIZE``.

    ::

        VOLUME_GROUP="stack-volumes"
        VOLUME_NAME_PREFIX="volume-"
        VOLUME_BACKING_FILE_SIZE=10250M

Multi-host DevStack
-------------------

Running DevStack with multiple hosts requires a custom ``local.conf``
section for each host. The master is the same as a single host
installation with ``MULTI_HOST=True``. The slaves have fewer services
enabled and a couple of host variables pointing to the master.

Master
~~~~~~

Set ``MULTI_HOST`` to true
    ::

        MULTI_HOST=True

Slave
~~~~~

Set the following options to point to the master

    ::

        MYSQL_HOST=w.x.y.z
        RABBIT_HOST=w.x.y.z
        GLANCE_HOSTPORT=w.x.y.z:9292
        ENABLED_SERVICES=n-vol,n-cpu,n-net,n-api

IP Version
----------

``IP_VERSION`` can be used to configure DevStack to create either an
IPv4, IPv6, or dual-stack tenant data-network by with either
``IP_VERSION=4``, ``IP_VERSION=6``, or ``IP_VERSION=4+6``
respectively.  This functionality requires that the Neutron networking
service is enabled by setting the following options:

    ::

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

The following optional variables can be used to alter the default IPv6
behavior:

    ::

        IPV6_RA_MODE=slaac
        IPV6_ADDRESS_MODE=slaac
        FIXED_RANGE_V6=fd$IPV6_GLOBAL_ID::/64
        IPV6_PRIVATE_NETWORK_GATEWAY=fd$IPV6_GLOBAL_ID::1

*Note*: ``FIXED_RANGE_V6`` and ``IPV6_PRIVATE_NETWORK_GATEWAY`` can be
configured with any valid IPv6 prefix. The default values make use of
an auto-generated ``IPV6_GLOBAL_ID`` to comply with RFC4193.

Service Version
~~~~~~~~~~~~~~~

DevStack can enable service operation over either IPv4 or IPv6 by
setting ``SERVICE_IP_VERSION`` to either ``SERVICE_IP_VERSION=4`` or
``SERVICE_IP_VERSION=6`` respectively.

When set to ``4`` devstack services will open listen sockets on
``0.0.0.0`` and service endpoints will be registered using ``HOST_IP``
as the address.

When set to ``6`` devstack services will open listen sockets on ``::``
and service endpoints will be registered using ``HOST_IPV6`` as the
address.

The default value for this setting is ``4``.  Dual-mode support, for
example ``4+6`` is not currently supported.  ``HOST_IPV6`` can
optionally be used to alter the default IPv6 address

    ::

        HOST_IPV6=${some_local_ipv6_address}

Examples
========

-  Eliminate a Cinder pass-through (``CINDER_PERIODIC_INTERVAL``):

   ::

       [[post-config|$CINDER_CONF]]
       [DEFAULT]
       periodic_interval = 60

-  Sample ``local.conf`` with screen logging enabled:

   ::

       [[local|localrc]]
       FIXED_RANGE=10.254.1.0/24
       NETWORK_GATEWAY=10.254.1.1
       LOGDAYS=1
       LOGDIR=$DEST/logs
       LOGFILE=$LOGDIR/stack.sh.log
       ADMIN_PASSWORD=quiet
       DATABASE_PASSWORD=$ADMIN_PASSWORD
       RABBIT_PASSWORD=$ADMIN_PASSWORD
       SERVICE_PASSWORD=$ADMIN_PASSWORD
       SERVICE_TOKEN=a682f596-76f3-11e3-b3b2-e716f9080d50