Make "cluster.deprecation_indexing.enabled" optional

Chart version: 7.16.1 (with Elasticsearch-Image 7.6.2)

Kubernetes version: 1.19.x

Kubernetes provider: E.g. GKE (Google Kubernetes Engine) Bare-Metal

Helm Version: 3.6.3

helm get release output not relevant

Describe the bug: The new helm-chart version introduced this new environment variable which is of course not supported by our underlying ES version (ES crashes then). We want to do this chart-update to get the new v1-Ingress in-place to do subsequent infrastructure updates.

Steps to reproduce:

1. Install the newest chart version with an older ES image version
2. ES won’t start

Expected behavior: The “cluster.deprecation_indexing.enabled” parameter should be made optional.

Provide logs and/or server output (if relevant):

Be careful to obfuscate every secrets (credentials, token, public IP, …) that could be visible in the output before copy-pasting

Any additional context:

[jmlrt]

Yes, I understand and totally agree that updating Elasticsearch version may not be an option in certain cases, and meanwhile, new K8S versions are bringing changes that may not be compatible with the previous chart version.

However, we don’t have the bandwidth to maintain backward compatibility and support for every use case, so a choice had to be made to support only the current version with chart version == Elasticsearch version.

For the other use case, we recommend forking these charts and integrating the changes in your fork.

[phoenix-bjoern]

I don’t agree that the Helm chart and application version have to be aligned. There are good examples that BC plays a role and is respected in the existing chart, like esMajorVersion. And I would appreciated if toggles/switches specific to an ES version would be introduced wisely in the chart.