**To upgrade ScyllaDB:**

#. Update the |APT|_ to **2022.x**.
#. Install:

    .. code:: sh

       sudo apt-get clean all
       sudo apt-get update
       sudo apt-get dist-upgrade scylla-enterprise

Answer ‘y’ to the first two questions.

Start the node
--------------

.. code:: sh

   sudo service scylla-server start

Validate
--------
#. Check cluster status with ``nodetool status`` and make sure **all** nodes, including the one you just upgraded, are in UN status.
#. Use ``curl -X GET "http://localhost:10000/storage_service/scylla_release_version"`` to check the ScyllaDB version.
#. Check scylla-server log (by ``journalctl _COMM=scylla``) and ``/var/log/syslog`` to validate there are no errors.
#. Check again after 2 minutes to validate no new issues are introduced.

Once you are sure the node upgrade is successful, move to the next node in the cluster.

Rollback Procedure
==================

.. include:: /upgrade/_common/warning_rollback.rst

The following procedure describes a rollback from ScyllaDB Enterprise release 2022.x.z to 2022.x.y. Apply this procedure if an upgrade from 2022.x.y to 2022.x.z failed before completing on all nodes. Use this procedure only for nodes you upgraded to 2022.x.z.

ScyllaDB rollback is a rolling procedure which does **not** require a full cluster shutdown.
For each of the nodes rollback to 2022.x.y, you will:

* Gracefully shutdown ScyllaDB
* Downgrade to the previous release
* Restore the configuration file
* Restart ScyllaDB
* Validate the rollback success

Apply the following procedure **serially** on each node. Do not move to the next node before validating that the node is up and running the new version.

Rollback Steps
==============

Gracefully shutdown ScyllaDB
-----------------------------

.. code:: sh

   nodetool drain
   sudo service scylla-server stop

Downgrade to the previous release
----------------------------------

Install:

.. code:: sh

   sudo apt-get install scylla-enterprise=2022.x.y\* scylla-enterprise-server=2022.x.y\* scylla-enterprise-jmx=2022.x.y\* scylla-enterprise-tools=2022.x.y\* scylla-enterprise-tools-core=2022.x.y\* scylla-enterprise-kernel-conf=2022.x.y\* scylla-enterprise-conf=2022.x.y\* scylla-enterprise-python3=2022.x.y\*
   sudo apt-get install scylla-enterprise-machine-image=2022.x.y\*  # only execute on AMI instance

Answer ‘y’ to the first two questions.

Restore the configuration file
------------------------------

.. code:: sh

   sudo rm -rf /etc/scylla/scylla.yaml
   sudo cp -a /etc/scylla/scylla.yaml.backup-2022.x.z /etc/scylla/scylla.yaml

Restore more config files.

.. code:: sh

   for conf in $(cat /var/lib/dpkg/info/scylla-*server.conffiles /var/lib/dpkg/info/scylla-*conf.conffiles /var/lib/dpkg/info/scylla-*jmx.conffiles | grep -v init ); do sudo cp -v $conf.backup-2.1 $conf; done
   sudo systemctl daemon-reload

Start the node
--------------

.. code:: sh

   sudo service scylla-server start

Validate
--------
Check the upgrade instruction above for validation. Once you are sure the node rollback is successful, move to the next node in the cluster.
