Hi all -
I don't seem to need any help after all, but thought I'd at least record the experience.
The problem I had been having was on my mythbackend machine:
- after an update, the local mythfrontend was returning 'unable to connect to database'
- I was able to log in to mysql using the credentials and the local port
- in the recovery screen, choosing the 'setup' option showed the wrong IP address
- wrong in the sense that it was an external LAN (192.168 etc) address, not ::1, and
- wrong in the sense that this system was no longer 192.168.1.13 (which was what the recovery file had).
- I checked /etc/mythtv/config.xml and /home/mythtv/.mythtv/config.xml and my user account config.xml and ensured all were set to ::1.
- remote frontend on Kodi on Raspbian works; but the local frontend was still failing.
but the problem persists: mythfrontend can't find database.
so I ran a sudo find / -name config?xml
I found one more in a tmp subdirectory. It too had a correct IP address, but I rm-ed it.
Then I came to post my problem, ran mythfrontend expecting no change, and the darn has thing fired up.
My current theory is that letting Ubuntu 18.04 resurrect mythfrontend when it mistakes "exiting the recovery screen without getting mythfrontend up and running" for "experiencing a crash" and subsequently trying to edit config.xml files with it open was my mistake. Happy to learn something if you can make more sense of this ridiculous account.