See the `3.X <https://doc.powerdns.com/3/authoritative/upgrading/>`__
upgrade notes if your version is older than 3.4.2.
+4.1.X to 4.2.0
+--------------
+
+- Superslave operation is no longer enabled by default, use :ref:`setting-superslave` to enable. This setting was called ``supermaster`` in some 4.2.0 prereleases.
+- The gsqlite3 backend, and the DNSSEC database for the BIND backend, have a new journal-mode setting. This setting defaults to `WAL <https://www.sqlite.org/wal.html>`_; older versions of PowerDNS did not set the journal mode, which means they used the SQLite default of DELETE.
+
4.1.0 to 4.1.1
--------------