Hmm, not seen this one before. Happy to try to help.
It sounds like the build of Discourse needs a newer version of Docker. This is either an error with the
launcher script - presumably that’s a shell script that’s part of Discourse - or maybe Docker has detected that a new build image is not compatible with the current version. I’ve not heard of the latter, but it is quite possible.
Am I right that the database and settings for Discourse are outside of this image, either in another container or in an on-host volume? Getting a backup in place is the first thing, I would say.
My guess is that once you have a backup you’re happy with, you just need to:
- Update the host to the latest Docker, either from your distro’s upstream version, or one from the Docker repo (Ubuntu/Debian etc allow the Docker repo to be added to your trusted repos list, so you get the latest stable version)
- Restart Docker or Docker Compose
- If you are in doubt, you could copy everything to a laptop and try it there first.
I’m sure some downtime would be fine, so it’s not like it has to be done in a rush
Happy to help over a beer, if that’s of use!