JerryMX

Um, OK. I have no interest in upgrading in-place and can easily avoid "wasting space," just want to protect development stages. But for people who do, your advice sounds like it would be useful.

Thanks for answering this, much appreciated! I'm on MX Linux (Debian 11 base) and knew about dd. The nice part about the RPi software I mentioned is that a backup or copy can be made directly from the running system, saving a lot of futzing around. If I can't work that out, I will first try rsync/grsync for an incremental backup--but not sure the copy would be functional.

What is the recommended way to back up a user's *.img? I ask b/c I crashed the OS (Debian 11 Xfce) after a number of hours by upgrading via Synaptic -- don't know which of the upgrade group did the damage. It was a major pain to go back through everything I had done. I tried the very nice script "image-backup" from the image-utils developed by user RonR on the RPi Forum, but it complains about the wrong Partition config. Is there a method that is known to work? TIA