Configure kubelet parameters via BR API

[nkvetsinski]

What I'd like:

Our team needs to change some of the kubelet parameters (in our case we change -v --client-ca-file, --tls-cert-file, --tls-key-file). We would like to have these parameters exposed to the API, ideally all of the flags can be changed.

Any alternatives you've considered:

To unblock our usecase we have created privileged host container that changes KubeletConfig file on the filesystem.

[stmcginnis]

Thanks @nkvetsinski - this looks like good functionality to support. I don't have any timeframe yet, but I'll take a look and I should be able to get to this soon(ish!).

^^ That said, if any community members are interested in picking this up, just let me know. :)

[stmcginnis]

Small update, the -v parameter for adjusting logging level is included in the v1.10.0 release with #2460

[nkvetsinski]

Sweet!

[stmcginnis]

Here are the equivalent Bottlerocket settings:

Existing

Kublet Arg	Bottlerocket Setting
-v	settings.kubernetes.log-level
--client-ca-file	settings.kubernetes.cluster-certificate

New in v1.11.0 (or whichever release after #2536 lands)

Kublet Arg	Bottlerocket Setting
--tls-cert-file	settings.kubernetes.server-certificate
--tls-key-file	settings.kubernetes.server-key

All cert settings take the base64 content of the files that will be decoded and written out on the host and the kubelet configuration will be updated to point to those local files.

Disclaimer: New setting names are subject to change based on review feedback. Will try to remember to edit/update this comment with any changes.

[stmcginnis]

Updated the previous comment with the final names of the settings. This should be in the v1.11.0 release.