As of version 2.5, net-dns/knot has changed DNSSEC key database format from JSON to LMDB. They ship a conversion script, "pykeymgr", to manage the transition; see https://www.knot-dns.cz/docs/2.5/html/migration.html#kasp-db-migration Trying to run pykeymgr from net-dns/knot-2.5.2 results in the following error: # pykeymgr -i /var/lib/knot/keys/ Error: unable to import module LMDB. Probably you need to 'pip install lmdb' or so. Installing dev-python/lmdb makes it work. Please add that as a dependency.
confirmed by Pierre-Olivier Mercier
The dependency was added in net-dns/knot-2.5.3-r1. See: https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=23ea15709bcec6a836430ae59450a9cbeccc569a Thanks for the report!