.. _controlcenter_upgrade:

Upgrading Control Center
========================

.. important::
  * By default, the upgrade process will preserve the last 15 minutes of historical data. We have two properties that allow you to control how much history will be preserved: ``confluent.metrics.topic.skip.backlog.minutes`` for broker metrics and ``confluent.monitoring.interceptor.topic.skip.backlog.minutes`` for stream monitoring. Preserving history for longer will slow down restore time of |c3-short| after the upgrade, while preserving less history will speed the process up.
  * Every version of |C3| (even minor upgrades) will re-create a new set of topics, since topic names contain the full version number. It is a good idea to remove the old ones to avoid confusion.
  * For |cp| version compatibility, see the :ref:`compatibility matrix <c3-cp-compatibility>`.

Upgrading from version 3.1.x and later
--------------------------------------

#. Upgrade |ak-tm| brokers to your target |cp| release. Follow instructions in :ref:`Confluent Platform Upgrade Guide <upgrade>`.

#. Upgrade the monitoring interceptors in all |ak| clients to your target |cp| version (this is optional if you are using |cp| interceptors 3.1 version and later).

#. Stop the |c3-short| process.

#. Make a backup of your current version configuration file. For example, copy and rename as ``control-center-3.1.properties``.

   .. codewithvars:: bash

          sudo cp /etc/confluent-control-center/control-center.properties /etc/confluent-control-center/control-center-3.1.properties

#. Upgrade |c3-short| packages to your target version.

#. Edit the |c3-short| properties file.  :ref:`Configuration property names <controlcenter_configuration>` may have changed between versions.

   * If you are running against a secured cluster you need to update your :ref:`security configs<kafka_encryption_authentication_authorization_settings>`.
     Properties named ``confluent.controlcenter.streams.{producer,consumer}.{sasl,ssl}.*`` are now ``confluent.controlcenter.streams.{sasl,ssl}.*``
   * You can control the amount of historical stream monitoring data |c3-short| will process after the upgrade (which can take some time), by setting
     ``confluent.metrics.topic.skip.backlog.minutes`` for broker metrics and ``confluent.monitoring.interceptor.topic.skip.backlog.minutes`` for stream
     monitoring. They default to 15 minutes. Setting them to shorter period will allow |c3-short| to catch up and show current data faster, at the expense
     of not processing old data.

#. Start |c3-short|.

   .. codewithvars:: bash

          <path-to-confluent>/bin/control-center-start <path-to-confluent>/etc/confluent-control-center/control-center.properties


Upgrading from version 3.0.x
----------------------------

#. Upgrade |ak| brokers to |cp| 3.1

#. Upgrade the monitoring interceptors in all |ak| clients to |cp| 3.1

#. Stop the |c3-short| process

#. Copy the 3.0.x configuration file

   .. codewithvars:: bash

          sudo cp /etc/confluent-control-center/control-center.properties /etc/confluent-control-center/control-center-3.0.properties

#. Upgrade |c3-short| packages to |cp| 3.1

#. Reset the application (deleting internal state)

   .. codewithvars:: bash

          # Use the same properties file you used to launch |c3-short|
          # From 3.0.1
          /usr/bin/control-center-3_0_1-reset /etc/confluent-control-center/control-center-3.0.properties
          # From 3.0.0
          /usr/bin/control-center-3_0_0-reset /etc/confluent-control-center/control-center-3.0.properties

#. Edit the |c3-short| properties file.  Some :ref:`configuration property names <controlcenter_configuration>` have changed

   * If you had set the ``confluent.controlcenter.name`` parameter, we suggest changing the value to reflect the new version (e.g. _confluent-controlcenter-3-1-0). This isn't strictly necessary but a good precaution in case any step of the reset failed.
   * You can control the amount of historical stream monitoring data |c3-short| will process after the upgrade (which can take some time), by setting ``confluent.metrics.topic.skip.backlog.minutes`` for broker metrics and ``confluent.monitoring.interceptor.topic.skip.backlog.minutes`` for stream monitoring. They default to 15 minutes. Setting them to shorter period will allow |c3-short| to catch up and show current data faster, at the expense of not processing old data.


#. Start |c3-short|

   .. codewithvars:: bash

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