Document timezones setup (#33)

source/index.rst

@@ -16,5 +16,6 @@ This documentation presents `GLPI <http://glpi-project.org>`_ installation instr
    prerequisites
    install/index
    install/wizard
+   timezones
    update
    command-line

source/timezones.rst

@@ -0,0 +1,43 @@
+Timezones
+=========
+
+In order to get timezones working on a MariaDB/MySQL instance, you will have to initialize Timezones data and grant GLPI database user read ACL on their table.
+
+.. warning::
+
+   Enabling timezone support on your MySQL instance may affect other database in the same instance; be carefull!
+
+Non windows users
+-----------------
+
+On most systems, you'll have to initialize timezones data from your system's timezones:
+
+.. code-block:: bash
+
+   mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql -p -u root mysql
+
+You may want to check `MariaDB documentation about mysql_tzinfo_to_sql <https://mariadb.com/kb/en/library/mysql_tzinfo_to_sql/>`_ and your system documentation do know where data are stored (if not in ``/usr/share/zoneinfo``).
+
+Do not forget to restart the database server once command is successfull.
+
+Windows users
+-------------
+
+Windows does not provide timezones informations, you'll have to download and intialize data yourself.
+
+See `MariaDB documentation about timezones <https://mariadb.com/kb/en/library/time-zones/#mysql-time-zone-tables>`_.
+
+Grant access
+------------
+
+.. warning::
+
+   Be carefull not to give your GLPI database user too large access. System tables should **never** grant access to app users.
+
+In order to list possible timezones, your GLPI database user must have read access on ``mysql.time_zone_name`` table.
+Assuming your user is ``glpi@localhost``, you should run something like:
+
+.. code-block:: sql
+
+   GRANT SELECT ON `mysql`.`time_zone_name` TO 'glpi'@'localhost';
+   FLUSH PRIVILEGES;