sysext for k3s or rke2?

[kastl-ars]

Hi all,

I just read the docs on the "new" sysext capabilities. I found one issue on packaging Podman as a sysext.

Has anyone thought of having sysexts for k3s or rke2 kubernetes distributions that come with (more or less) a single binary?

• https://k3s.io/
• https://docs.rke2.io/

Especially k3s is really nice on limited hardware, so combining this with Flatcar would be really interesting.

Kind Regards,
Johannes

[ader1990]

Hello @kastl-ars,

K3s systemd-sysext support has been just added a few days ago: flatcar/sysext-bakery#53.

[kastl-ars]

Thanks, nice to hear that.
That sysext just contains the binary, are the service files in a confext or are they left out intentionally?

If I find time on the weekend, I could come up with a similar script for rke2...

[tormath1]

@kastl-ars confext are not yet tested / supported at the moment on Flatcar. IIRC k3s takes care of installing his own systemd units? If you think of configuration inside /etc you can provide additional units that takes care of linking / copying files from /usr to /etc or use systemd-tmpfiles (e.g: https://github.com/flatcar/scripts/blob/59842e9ee706a039d708cb655d285fecba20bca4/build_library/sysext_mangle_flatcar-zfs#L30-L36)

[kastl-ars]

IIRC k3s takes care of installing his own systemd units?

Not as far as I know. The script that can be used to install/download k3s can do that.

Regarding the confext, I thought that for some reason the unit files need to go to /etc/ and thus were omitted from the sysext. Normally they should be in /usr/lib/systemd/system/.

[kastl-ars]

I opened a PR to add rke2: flatcar/sysext-bakery#68

And I opened another PR to add the k3s service files: flatcar/sysext-bakery#69

Both are using /usr/bin/local to a) match upstream and b) separate sys-ext installed binaries from system binaries.