Have you rebooted? I’ve had trouble with Docker if I’ve done an upgrade and didn’t reboot.
Yeah. That’s scary-sounding. I know that I have sites on 16.04 and know that I haven’t done anything with runc.
If you’re concerned about down time and you’re on Digital Ocean, you might just
- spin up a new droplet with 18.04 and do a clean install.
- Get an floating IP, point it at the old server, and point DNS there.
- Put the old forum in read-only
- back up
- restore to the new server
- re-point the floating IP to the new server.
You’ll have no down time and just the read-only time it takes to back up and restore. You can practice a time or two before you do the read-only bit. You could also rsync uploads rather than including them in the backup, so you’d need to backup/restore just the database.
You’d probably want to pull over your existing let’s encrypt certs too, though, or, I think, you’ll have to rebuild to get them.