Specify which server version is contained in each tag?

[gbakeman]

Thank you for providing this docker image for us to use the NUT server with. I'm looking for a specific server version to test, but it's unclear to me how the tags (formatted year.month) match up with server releases. You mention in the notes, "NUT version tracks whatever Debian stable ships (currently bookworm), not the upstream latest", although this doesn't really tell me much from the standpoint of looking at the tags on this image. Is there a chance you could document how the server versions related to your tagged releases?

[Nardo86]

Thanks for raising this — it was a fair gap, and I've now fixed it.

Short answer: the YYYY.MM tags are build dates, not NUT versions. The server comes from Debian's nut-server package, so its version is whatever Debian stable ships — currently 2.8.0-7 (upstream 2.8.0) on bookworm. That upstream version stays frozen for the whole bookworm lifecycle; only Debian point-release/security patches change between the monthly rebuilds. It'll jump to a newer upstream only when I move the base image to the next Debian stable (trixie).

Version tags are now live on Docker Hub, so you can pin the exact server version you want to test:

Tag	NUT version
2.8.0-7 / 2.8.0	current bookworm line (upstream 2.8.0)
2.7.4-13 / 2.7.4	previous bullseye line (the 2025.06–2025.10 tags)

X.Y.Z-R pins the exact Debian package revision; X.Y.Z follows the newest revision of that upstream version. So docker pull nardo86/nut-server:2.8.0 gets you exactly 2.8.0.

Going forward the build resolves and tags by the packaged NUT version automatically, and stamps it into an OCI label so you can check any tag without even pulling it:

docker inspect --format '{{ index .Config.Labels "org.networkupstools.version" }}' nardo86/nut-server:2.8.0
# or straight from the binary:
docker run --rm --entrypoint upsd nardo86/nut-server:2.8.0 -V

The two-axis tag scheme (which NUT version vs. which build) is now documented in the README — see #4.

[gbakeman]

That's fantastic, thank you so much for making this change.