Unexpected behaviour around controller.minAvailable and controller.maxUnavailable parameters

[qlikcoe]

As of chart version 4.4.2 new PDB parameter was introduced: controller.maxUnavailable.

Here's the code snipped of how it was implemented:

{{- if .Values.controller.minAvailable }}
  minAvailable: {{ .Values.controller.minAvailable }}
{{- else if .Values.controller.maxUnavailable }}
  maxUnavailable: {{ .Values.controller.maxUnavailable }}
{{- end }}

Because the default values.yaml has controller.minAvailable set to 1, the conditional block above doesn't work as expected, unless you explicitly override controller.minAvailable: null during helm chart deployment. Otherwise it will ignore the maxUnavailable.

The documentation for these two PDB parameters is also not aligned with how it behaves. It says:

Define either 'minAvailable' or 'maxUnavailable', never both.

The readme is also missing the description for the maxUnavailable parameter, the latter is only mentioned in the description of the minAvailable parameter:
https://github.com/kubernetes/ingress-nginx/blob/main/charts/ingress-nginx/README.md?plain=1#L392

[k8s-ci-robot]

This issue is currently awaiting triage.

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[github-actions]

This is stale, but we won't close it automatically, just bare in mind the maintainers may be busy with other tasks and will reach your issue ASAP. If you have any question or request to prioritize this, please reach #ingress-nginx-dev on Kubernetes Slack.

[balonik]

This bug is really annoying.