Second ssh server on each host
Not all my boxes are migrated to OpenBSD, some are still running Debian..
After an upgrade of Debian Stretch to Debian Buster borked the ssh server on that box, which locked me out of the machine, an collegue adviced me, to run two different ssh servers on each box, f,e., openssh and dropbear.
This way, if one of the ssh servers stops functioning, you can still use the other to log on to your system.
He is a seasoned Linux admin, and he told me he does run two different ssh servers on all his boxes.
So, we could consider this as some kind of best practice.
To me, it seems like a good idea, and I will do that on all my Debian boxes from now on.