Explicitly document the Kubernetes version compatibility for each ArgoCD release in a single location

[sigwinch28]

Summary

In a single table in the documentation, create a table which states for every ArgoCD minor version which kubernetes versions it is compatible with.

Motivation

I am running a version of Kubernetes which isn't the latest. I want to install ArgoCD on it and I want to quickly find out which versions of ArgoCD I can use, even if the Kubernetes version is unsupported and the ArgoCD version is unsupported. I looked at https://argo-cd.readthedocs.io/en/stable/operator-manual/installation/#supported-versions which contains an example and a formula for calculating which versions are supported, but I find it very confusing:

Similar to the Kubernetes project, the supported versions of Argo CD at any given point in time are the latest patch releases for the N and N - 1 minor versions. These Argo CD versions are supported on the same versions of Kubernetes that are supported by Kubernetes itself (normally the last 3 released versions).

Essentially the Argo CD project follows the same support scheme as Kubernetes but for N, N-1 while Kubernetes supports N, N-1, N-2 versions.

Proposal

Put a table in the documentation site similar to the cert-manager compatibility table:

For example (with made-up numbers):

ArgoCD release	Compatible kubernetes versions
2.5	1.24 - 1.26
2.4	1.24 - 1.26
2.3	1.23 - 1.25
2.2	1.22 - 1.24

and so on...

[wlieberz]

I would love to see this get prioritized. I fully agree that the current verbiage is very confusing. I would suggest the version compatibility table should be prominently featured in the README.md as well as in the docs. Thank you!

[SnoozingPinata]

Please add this. Upgrading argo-cd becomes a nightmare when you have to juggle several different application and kubernetes version compatibilities. This information needs to be easily accessible so that you can quickly find what version(s) will work for you.

Edit:

I have added the last few release dates for kubernetes minor versions and argo-cd minor versions. For each argo-cd release, the previous 3 kubernetes releases should be compatible based on the documentation here: https://argo-cd.readthedocs.io/en/stable/operator-manual/installation/#supported-versions

yyyy/mm/dd - project - release
2023/05/01 - argo - 2.7.0
2023/04/11 - K8s - 1.27.0
2023/02/06 - argo - 2.6.0
2022/12/09 - K8s - 1.26.0
2022/10/25 - argo - 2.5
2022/08/23 - K8s - 1.25.0
2022/05/03 - K8s - 1.24.0
2021/12/07 - K8s - 1.23.0
2021/08/04 - K8s - 1.22.0

[crenshaw-dev]

I think we need automation to build this table added to the release workflow. There's already a step which opens a PR to update version numbers in the release branch. The same step could be augmented to generate the table and add it to docs.

[crenshaw-dev]

This information now lives here: https://argo-cd.readthedocs.io/en/latest/operator-manual/installation/#tested-versions

[Whisper40]

@crenshaw-dev Hello, any update of the page ?

[sl3dg3hamm3r]

@crenshaw-dev Are there any updates regarding compatibility soon? https://argo-cd.readthedocs.io/en/latest/operator-manual/installation/#tested-versions

[Whisper40]

Yes the correct link is : https://argo-cd.readthedocs.io/en/stable/operator-manual/installation/#tested-versions