Memcached
~~~~~~~~~

The Identity service authentication mechanism for services uses Memcached
to cache tokens. The memcached service typically runs on the controller
node. For production deployments, we recommend enabling a combination of
firewalling, authentication, and encryption to secure it.

Install and configure components
--------------------------------

#. Install the packages:

   .. only:: ubuntu

      .. code-block:: console

         # apt-get install memcached python-memcache

   .. only:: rdo

      .. code-block:: console

         # yum install memcached python-memcached

   .. only:: obs

      .. code-block:: console

         # zypper install memcached python-python-memcached

.. only:: ubuntu

   2. Edit the ``/etc/memcached.conf`` file and configure the
      service to use the management IP address of the controller node
      to enable access by other nodes via the management network:

      .. code-block:: ini

         -l 10.0.0.11

      .. note::

         Change the existing line with ``-l 127.0.0.1``.

Finalize installation
---------------------

.. only:: ubuntu or debian

   * Restart the Memcached service:

     .. code-block:: console

        # service memcached restart

.. only:: rdo or obs

   * Start the Memcached service and configure it to start when the system
     boots:

     .. code-block:: console

        # systemctl enable memcached.service
        # systemctl start memcached.service