.. _c3_properties_files:

###########################
|c3-short| properties files
###########################

.. meta::
  :title: Confluent Control Center configuration properties files
  :description: This document describes the available properties files for 
                configuring options and features in Confluent Control Center
                environments. Pass in properties files when starting Control 
                Center.
  :keywords: Confluent Control Center, configuration properties files, 
             control-center.properties, control-center-dev.properties, 
             control-center-production.properties, control-center-minimal.properties,
             etc directory, stopping Control Center, starting Control Center, 
             restarting Control Center, passing a properties file

Several |c3-short| example properties files reside in the 
``etc/confluent-control-center`` directory located in your ``CONFLUENT_HOME`` 
directory. These files contain critical configuration options, 
some of which are set to defaults or commented out. Not all of the available 
configuration options are present in the properties files. For instance,
the majority of the :ref:`Access Control <controlcenter_access_control_settings>`
options are not present by default and must be added manually. Depending on the 
requirements of your environments, there are additional configuration options 
documented in the :ref:`controlcenter_configuration` that you can add and 
configure within your properties files. Defaults are typically different between 
the available properties file templates.

.. note:: Parameters are provided in the form of key/value pairs. Lines beginning 
          with ``#`` are ignored. To uncomment an option, remove the hash (pound) 
          that precedes it.

Available |c3-short| properties files:

``control-center.properties``
    Default properties file.

``control-center-dev.properties``
    Properties file for a development environment, including single broker under
    a :ref:`developer license <cp_developer_license>`. The dev properties file 
    is passed in by default with the ``start`` commands.

``control-center-production.properties``
    Properties file for a production environment. Options must be set for 
    production, such as a data directory other than ``/tmp``, hostnames set 
    rather than localhost, security features configured, and so forth.

``control-center-minimal.properties``
    Properties file optimized for a local environment. Typically used for laptop 
    demonstration purposes.

.. _c3_pass_props_files:

***************************************
Passing in a |c3-short| properties file
***************************************

By default, |c3-short| is aware of its properties files that reside in the 
``$CONFLUENT_HOME/etc/confluent-control-center`` directory and reads them 
automatically when restarting using CLI commands. It is not necessary to 
explicitly pass in the properties file name when starting |c3-short| unless:

- The properties file has a custom name. You might differentiate properties
  file names for testing purposes.
- The properties file does not reside in the default directory. |c3-short| needs
  the full path to the properties file in this case.
- The ``.minimal`` properties file must always be explicitly passed with a 
  ``start`` command.
- The properties file must always be passed in when using the bin start script.

.. _c3_restart:

Restarting |c3-short|
=====================

Follow these instructions for stopping and starting |c3-short|. Examples of 
passing in a properties file when necessary or not are provided.

.. include:: ../includes/c3-props-files-note.rst

Example 1: Standard production environment
------------------------------------------

Example restarting |c3-short| and passing in the default properties file for the 
configuration to take effect:

.. sourcecode:: bash

    ./bin/control-center-stop
    ./bin/control-center-start ../etc/confluent-control-center/control-center.properties

Example 2: Custom properties filename and location
--------------------------------------------------

Example starting |c3-short| with the bin start script and passing in a custom
properties filename and location:

.. sourcecode:: bash

   ./control-center-stop
   ./control-center-start /Users/myUserName/confluent/configs/c3.properties-rbac

The example assumes you are in the ``/bin`` directory.

Example 3: Local development environment
----------------------------------------

Example starting |c3-short| in a local (dev) environment with the local CLI. This
example assumes you have configured your ``$CONFLUENT_HOME``. There is no need to 
pass in the properties filename; |c3-short| passes in ``control-center-dev.properties``
automatically.

.. important:: Do not use :ref:`confluent_local` for production use.

.. sourcecode:: bash

   confluent local stop
   confluent local start


.. _c3_props_files_excerpt_diffs:

Example properties file excerpts
--------------------------------

This section shows a few fundamental differences between a development and 
production |c3-short| properties file.

Example excerpt from the production properties 
(``control-center-production.properties``) file:

.. code-block:: RST
   :linenos:
   :emphasize-lines: 5, 13

   ############################# Server Basics #############################

   # A comma-separated list of Apache Kafka cluster host names (required)
   # NOTE: should not be localhost
   #bootstrap.servers=kafka1:9092
   ...

   ############################# Control Center Settings ###################

   ...
   # Directory for Control Center to store data
   # NOTE: this should be changed to point to a reliable directory
   confluent.controlcenter.data.dir=/var/lib/confluent/control-center
   ...

Example excerpt from the development properties 
(``control-center-dev.properties``) file:

.. code-block:: RST
   :linenos:
   :emphasize-lines: 4, 12

   ############################# Server Basics #############################

   # A comma-separated list of Apache Kafka cluster host names (required)
   bootstrap.servers=localhost:9092
   ...

   ############################# Control Center Settings ###################

   ...
   # Directory for Control Center to store data
   # NOTE: this should be changed to point to a reliable directory
   confluent.controlcenter.data.dir=/tmp/confluent/control-center
   ...

   .. note:  The ``.dev`` file is pre-configured with 
             ``localhost`` where applicable.  The data directory points to 
             a ``/tmp`` directory.