.. _config:

Configuring Holland
===================

By default, Holland's configuration files reside in /etc/holland. The main
configuration file is holland.conf, however there are a number of other
configuration files for configuring default settings for providers and for
configuring backup sets.

Each configuration file has one ore more sections, defined by square
brackets Underneath each section, one or more configuration option
can be specified. These options are in a standard "option = value" format.
Comments are prefixed by the # sign.

Note that many settings have default values and, as a result, can either
be commented out or omitted entirely.

.. _config-global:

Global Config
-------------

The main configuration file (usually ``/etc/holland/holland.conf``) defines
both global settings as well as the active backup sets. It is divided into
two sections :ref:`[holland]<holland-config>` and :ref:`[logging]<logging-config>`.

.. _holland-config:

[holland]
^^^^^^^^^

.. _holland-config-plugin_dirs:

.. describe:: plugin_dirs = [directory1],[directory2],...,[directoryN]

    Defines where the plugins can be found. This can be a comma-separated
    list but usually does not need to be modified. For most installations,
    this will usually be ``/usr/share/holland/plugins``.

.. deprecated:: 1.0.8

    This option is no longer required and can be omitted.

.. _holland-config-backup_directory:

.. describe:: backup_directory = [directory]

    Top-level directory where backups are held. This is usually
    ``/var/spool/holland``.

.. _holland-config-backupsets:

.. describe:: backupsets = [backupset1],[backupset2],...,[backupsetN]

    A comma-separated list of all the backup sets Holland should backup.
    Each backup set is defined in ``/etc/holland/backupsets/<name>.conf`` by
    default.

.. describe:: umask = [0000-7777]

    Sets the umask of the resulting backup files.

.. describe:: path = <directory1>:<directory2>:...:<directoryN>

    Defines a path for holland and its spawned processes.

.. _logging-config:

[logging]
^^^^^^^^^

.. describe:: filename = [path]/[filename]

    The log file itself.

.. describe:: level = [debug|info|warning|error|critical]

    Sets the verbosity of Holland's logging process. Available options are
    ``debug``, ``info``, ``warning``, ``error``, and ``critical``

Example
^^^^^^^

.. code-block:: ini

    ## Root holland config file
    [holland]

    ## Paths where holland plugins may be found.
    ## Can be comma separated
    plugin_dirs = /usr/share/holland/plugins

    ## Top level directory where backups are held
    backup_directory = /var/spool/holland

    ## List of enabled backup sets. Can be comma separated.
    ## Read from <config_dir>/backupsets/<name>.conf
    # backupsets = example, traditional, parallel_backups, non_transactional
    backupsets = mydbbackup, pgdump-full, mysql-lvm-reportingdb

    # Define a umask for file generated by holland
    umask = 0007

    # Define a path for holland and its spawned processes
    path = /usr/local/bin:/usr/local/sbin:/bin:/sbin:/usr/bin:/usr/sbin

    [logging]
    ## where to write the log
    filename = /var/log/holland.log

    ## debug, info, warning, error, critical (case insensitive)
    level = info

.. _config-backupsets:

Backup-Set Configs
------------------
Backup-Set configuration files are housed in ``/etc/holland/backupsets`` with
the name of the backup-set being the name of the file before the .conf suffix
(e.g. 'myfavoritebackup.conf' is the configuration file for the
'myfavoritebackup' backup-set).

The backups themselves are placed under the directory defined in the
:ref:`backup_directory<holland-config-backup_directory>` section of the main
configuration file. Each backup resides under a directory corresponding to the
backup-set name followed by one or more date-encoded directories.

Backup-Set configuration files inherit the configuration options of
the specified plugins (though these settings can be overridden). To define a
provider plugin for the backup set, you must put the following at the top of the
backup set configuration file.

.. code-block:: ini

    [holland:backup]
    plugin = <plugin>
    backups-to-keep = #
    estimated-size-factor = #

.. _holland-backup-config_options:

[holland:backup] Configuration Options
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This section is for configuring Holland specific options and is usually at the
top of a particular backup set configuration file. These options control the
behavior of Holland itself, rather than of the backup provider and associated
helper plugins (which are defined within their own sections - see below).

.. describe:: plugin = [provider plugin]

    This is the name of the provider that will be used for the backup-set.
    This is required in order for the backup-set to function.

.. describe:: backups-to-keep = #

    Specifies the number of backups to keep for a backup-set.
    Defaults to retaining 1 backup.

.. describe:: estimated-size-factor = #

    Specifies the scale factor when Holland decides if there is enough
    free space to perform a backup.  The default is 1.0 and this number
    is multiplied against what each individual plugin reports its
    estimated backup size when Holland is verifying sufficient free
    space for the backupset.

.. describe:: auto-purge-failures = [yes|no]

    Specifies whether to keep a failed backup or to automatically remove
    the backup directory.  By default this is on with the intention that
    whatever process is calling holland will retry when a backup fails.
    This behavior can be disabled by setting auto-purge-failures = no when
    partial backups might be useful or when troubleshooting a backup failure.

.. describe:: purge-on-demand = [yes|no]

   If enabled, this option will cause holland to attempt to purge old backups
   within the same backupset to free enough space to allow a new backup to
   start rather than failing when it appears that there is insufficient space
   to run a new backup.  If the space consumed by all purgable backups is less
   than the estimated space for a new backup, no backups are purged as the
   new backup will fail regardless.

.. describe:: purge-policy = [manual|before-backup|after-backup]

    Specifies when to run the purge routine on a backupset.  By default this is
    run after a new successful backup completes.  Up to ``backups-to-keep``
    backups will be retained including the most recent.

    ``purge-policy = before-backup`` will run the purge routine just before
    a new backup starts.  This will retain up to ``backups-to-keep`` backups
    before the new backup is even started allowing purging all previous
    backups if ``backups-to-keep`` is set to 0.  This behavior is useful if
    some other process is retaining backups off-server and disk space is at a
    premium.

    ``purge-policy = after-backup`` will run the purge routine after the
    completion of the backup. This means more space is required during the
    backup run. This is safer than ``before-backup`` due to failed backups not
    causing good backups to be purged.

    ``purge-policy = manual`` will never run the purge routine automatically.
    Either ``holland purge`` must be run externally or an explicit removal of
    desired backup directories can be done at some later time.

Hooks
"""""

.. describe:: before-backup-command = string

    Run a shell command before a backup starts, such as setting up an iptables
    rule (taking a mysql slave out of a load balancer) or aborting the backup
    based on some external condition.

    The backup will fail if this command exits with a non-zero status.

    .. versionadded:: 1.0.7

.. describe:: after-backup-command = string

    Run a shell command after a **successful** backup, such as sending out an
    e-mail or performing external post backup cleanup tasks (such putting a
    server back in a load balancer for example).

    Note if the backup fails, ``failed-backup-command`` will be run instead.
    Thus, if doing things like pulling the server out of a load-balancer,
    such commands should added to ``after-backup-command`` and
    ``failed-backup-command`` to avoid an inconsistent state.

    The backup will fail if this command exits with a non-zero status.

    .. versionadded:: 1.0.7

.. describe:: failed-backup-command = string

    Run a shell command if a backup failed, such as firing off an e-mail to
    notify relevant folks about the failure.

    .. versionadded:: 1.0.7

For all hook commands, Holland will perform simple text substitution
on the three parameters:

  * **hook**: The name of the hook being called (one of: ``before-backup-command``, ``after-backup-command``, ``failed-backup-command``)
  * **backupdir**: The path to the current backup directory (e.g. ``/var/spool/holland/mysqldump/YYYYmmdd_HHMMSS``)
  * **backupset**: The name of the backupset being run (e.g. ``mysql-lvm``)

For Example

.. code-block:: ini

    [holland:backup]
    plugin = mysqldump
    before-backup-command = /usr/local/bin/my-custom-script --hook ${hook} --backupset ${backupset} --backupdir ${backupdir}
    after-backup-command = echo ${backupset} completed successfully.  Files are in ${backupdir}
    failed-backup-command = echo "${backupset} failed!" | mail -s "${backupset} backup failed" sysadmins@example.com



Provider Plugin Configs
^^^^^^^^^^^^^^^^^^^^^^^

The following are the provider plugins that can be used in a backup-set.
These are used within their own braced section in the backup-set
configuration file. For specific information on how to configure a
desired provider, see the list below.

For advanced users, the defaults for each provider plugin can be changed
by editing the default configuration file for said provider. These files are
located in ``/etc/holland/providers`` by default.

MySQL Plugins
"""""""""""""
.. toctree::
    :maxdepth: 1

    mysqldump <provider_plugins/mysqldump>
    MySQL + LVM <provider_plugins/mysql-lvm>
    mysqldump + LVM <provider_plugins/mysqldump-lvm>
    Plugin for Percona XtraBackup <provider_plugins/xtrabackup>
    MySQL Client Helper Plugin <provider_plugins/mysqlconfig>

Other Plugins
"""""""""""""
.. toctree::
    :maxdepth: 1

    pgdump (PostgreSQL) <provider_plugins/pgdump>
    Example Plugin <provider_plugins/example>

Helper Plugins
""""""""""""""
.. toctree::
    :maxdepth: 1

    Compression Helper Plugin <provider_plugins/compression>

Backup Set Config Example
^^^^^^^^^^^^^^^^^^^^^^^^^

Here is an example backup set which uses mysqldump to backup all but a
few databases, in a one-file-per-database fashion. For more specific
examples, consult the documentation for the specific provider plugin you
wish to use (see above).

.. code-block:: ini

    [holland:backup]
    plugin = mysqldump
    backups-to-keep = 1
    auto-purge-failures = yes
    purge-policy = after-backup
    estimated-size-factor = 0.25

    [mysqldump]
    extra-defaults = no
    lock-method = auto-detect
    databases = *
    exclude-databases = "mydb", "myotherdb"
    exclude-invalid-views = no
    flush-logs = no
    flush-privileges = yes
    dump-routines = no
    dump-events = no
    stop-slave = no
    max-allowed-packet = 128M
    bin-log-position = no
    file-per-database = yes
    estimate-method = plugin

    [compression]
    method = gzip
    inline = yes
    level = 1

    [mysql:client]
    defaults-extra-file = ~/.my.cnf
