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Documentation/Upgrading/Upgrading-To-MaxScale-2.3.md

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+# Upgrading MariaDB MaxScale from 2.2 to 2.3
+
+This document describes possible issues when upgrading MariaDB
+MaxScale from version 2.2 to 2.3.
+
+For more information about MariaDB MaxScale 2.3, please refer
+to the [ChangeLog](../Changelog.md).
+
+Before starting the upgrade, we recommend you back up your current
+configuration file.
+
+### `passwd` is no longer accepted
+
+In the configuration file, passwords for monitors and services must be
+specified using `password`; the support for the earlier deprecated
+`passwd` has been removed. That is, the following
+```
+[The-Service]
+type=service
+passwd=some-service-password
+...
+
+[The-Monitor]
+type=service
+passwd=some-monitor-password
+...
+```
+must be changed to
+```
+[The-Service]
+type=service
+password=some-service-password
+...
+
+[The-Monitor]
+type=service
+password=some-monitor-password
+...
+```