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.. _backend-powerdns:

PowerDNS Backend
================

Designate Configuration
-----------------------

===============================  ====================================== ==============================================================
Parameter                        Default                                Note
===============================  ====================================== ==============================================================
domain_type                      NATIVE                                 PowerDNS Domain Type
also_notify                      []                                     List of additional IPs to send NOTIFYs to.
database_connection              sqlite:///$pystatepath/powerdns.sqlite Database connection string
connection_debug                 0                                      Verbosity of SQL debugging information. 0=None, 100=Everything
connection_trace                 False                                  Add python stack traces to SQL as comment strings
idle_timeout                     3600                                   timeout before idle sql connections are reaped
max_retries                      10                                     maximum db connection retries during startup.
                                                                        (setting -1 implies an infinite retry count)
retry_interval                   10                                     interval between retries of opening a sql connection
mysql_engine                     InnoDB                                 MySQL engine to use
sqlite_synchronous               True                                   If passed, use synchronous mode for sqlite
===============================  ====================================== ==============================================================


PowerDNS Configuration
----------------------

You need to configure PowerDNS to use the MySQL backend.

1. First enable the MySQL backend:

    launch = gmysql

2. Configure the MySQL database settings::

    gmysql-host=<host>
    gmysql-port=
    gmysql-dbname=<dbname>
    gmysql-user=<username>
    gmysql-password=<password>
    gmysql-dnssec=yes
    #gmysql-socket=<socket path>

.. note::
   PowerDNS can connect via socket or host/port.

3. Configure the options for designate-central - specifaclly "database_connection" to point to your MySQL database::

    [backend:powerdns]
    database_connection = mysql://<username>:<password>@<host>:<port>/<dbname>

4. Setup the database schema.

::

    $ designate-manage powerdns database-init
    $ designate-manage powerdns database-sync

5. Restart PowerDNS and it should be ready to serve queries using the MySQL database as the backing store.


PowerDNS deployment as hidden Master
------------------------------------

One deployment scenario can be that the PowerDNS backend will be used as a "hidden" Master DNS for other DNS servers to consume via AXFR.

Say you have 10.0.0.1 and 10.0.0.2 as slaves then configure the backend as follows in addition to other options::

    [backend:powernds]
    domain_type = MASTER
    also_notify = 10.0.0.1,10.0.0.2

.. note::
   This should mostly be used in connection with another backend acting as slave.