CI: alpine-arm64 build fails

[jameshcorbett]

The alpine-arm64 build (which only runs on master) is failing and has been for several months. This means that the docker manifest is not generated and so multi-architecture images (such as el9) are only tagged separately (like el9-amd64 and el9-arm64) rather than together.

  #8 [3/5] RUN sudo /scripts/install-deps.sh
  #8 0.056 .buildkit_qemu_emulator: /bin/sh: Invalid ELF image for this architecture
  #8 ERROR: process "/dev/.buildkit_qemu_emulator /bin/sh -c sudo /scripts/install-deps.sh" did not complete successfully: exit code: 255
  ------
   > [3/5] RUN sudo /scripts/install-deps.sh:
  0.056 .buildkit_qemu_emulator: /bin/sh: Invalid ELF image for this architecture
  ------
  Dockerfile:9
  --------------------
     7 |     # Install extra buildrequires for flux-sched:
     8 |     COPY scripts/ /scripts
     9 | >>> RUN sudo /scripts/install-deps.sh
    10 |     
    11 |     # Add configured user to image with sudo access:
  --------------------
  ERROR: failed to solve: process "/dev/.buildkit_qemu_emulator /bin/sh -c sudo /scripts/install-deps.sh" did not complete successfully: exit code: 255
docker-run-checks.sh: docker build failed

[jameshcorbett]

@trws do you know what the source of the issue is here?

[trws]

That looks like it's either not setting up the emulator correctly or it's not running the right container architecture on the emulator. Likely the latter since it's saying qemu was running and /bin/sh was the wrong architecture but I'm not 100% sure. Will take a look now and see if I can find it quickly.

[trws]

Not seeing it right off but the arm64 native runners for linux on public repos are in public preview, so we may be able to switch all the arm builds to actually run on arm. Will throw something together and see what we get. If nothing else it should be substantially faster.

[trws]

They're the fastest runners, by almost half... This is crazy.

The fluxrm/flux-core:alpine image does not work currently:

~/Repos/flux/flux-sched arm-runners:master ⇡34 *12 ?60                                                                               ✘ 2 ▼  env
❯ docker run fluxrm/flux-core:alpine --platform=linux/arm64 /bin/bash
sudo: runuser: command not found
/usr/local/sbin/entrypoint.sh: exec: line 3: illegal option --

Tracing this back but there's going to need to be some work in core most likely.