https://knot-resolver.readthedocs.io/en/v4.0.0/upgrading.html#upgrade-from-3-to-4
- configuration: trust_anchors aliases .file, .config() and .negative were removed (!788)
- configuration: trust_anchors.keyfile_default is no longer accessible (!788)
+- daemon: -k/--keyfile and -K/--keyfile-ro options were removed
- meson build system is now used for builds (!771)
- build with embedded LMBD is no longer supported
- default modules dir location has changed
* DNSSEC validation is now turned on by default. If you need to disable it, see
:ref:`dnssec-config`.
+* ``-k/--keyfile`` and ``-K/--keyfile-ro`` daemon options were removed. If needed,
+ use ``trust_anchors.add_file()`` in configuration file instead.
* In case you are using your own custom modules, move them to the new module
location. The exact location depends on your distribution. Generally, modules previously
in ``/usr/lib/kdns_modules`` should be moved to ``/usr/lib/knot-resolver/kres_modules``.