.. _restarting-nodes:

============================
Restarting the cluster nodes
============================

To restart a cluster node, shut down MySQL and restarting it.
The node should leave the cluster
(and the total vote count for :term:`quorum` should decrement).

When it rejoins, the node should synchronize using :term:`IST`.
If the set of changes needed for IST are not found in the :file:`gcache` file
on any other node in the entire cluster,
then :term:`SST` will be performed instead.
Therefore, restarting cluster nodes for rolling configuration changes
or software upgrades is rather simple from the cluster's perspective.  

.. note:: If you restart a node with an invalid configuration change
   that prevents MySQL from loading, Galera will drop the node's state
   and force an SST for that node.

