Update K8s compatibility in test-plan and docs

[sabbyanandan]

As we continue to increase the ATs on different K8s versions, let's attempt to keep the K8s compatibility versions published in the docs and the CI plans correctly. Perhaps (re)use the same docs (same source) across the board. A few links are below.

• Update to run against 1.21.x and later versions (see: tmc-ci.yml)
• Update README
• Update PRO docs
• Update Microsite docs

[onobc]

tmc-ci.yml

Currently the TMC matrix has the most tested permutations for the latest version and then a few variations tested for the earlier versions.

Plan: We will update the current 1.20 entries to point to 1.21 and then keep a few entries for 1.20.

ℹ️ We are still not able to see 1.21 in the k8s version drop-down in TMC but it should be available/visible soon.

ℹ️ 1.21 is the latest available version in TMC. Once 1.22 is available, we will repeat this exercise for 1.22.

[onobc]

README

Plan: Expand grid to 1.21.x.

Question: Is the intention that the k8s version in the SCDK matrix be the same as the k8s version in the SCDF matrix? I would assume so. Do we have any compat matrix tests directly for SCDK or do we imply its coverage via the results of the SCDF TMC matrix tests? I am guessing the latter, but want to verify.

[onobc]

Microsite docs

Plan: Expand grid to 1.21.x

[onobc]

PRO docs

Question: The Pro docs tout support up to v1.22.x - does this need updating? Is the intention to pare it back down to what we are currently testing against (up to v1.21.x)? Or is the intention to bump it up to v1.23.x (latest k8s) based on the following comment in the docs :

This product is intended to be used with any Kubernetes distribution. However, given the number of Kubernetes vendors and configurations, not all of them have been tested with SCDF for Kubernetes.

If we do bump to v1.23.x should we manually verify?

[onobc]

I have left a separate comment (easier to reply to) on each of the "targeted" files in the original description.

@sabbyanandan @jvalkeal @ilayaperumalg (or other team members) please advise. Thx.

[onobc]

During IPM today we discussed the following:

1. Make the k8s version supported consistent in all places (the SCDK README matrix, the Microsite matrix, and the PRO docs)
2. Make the supported version be N to N-3 which is 1.21, 1.22, 1.23 and we add 1.20 as its recent enough
3. Remove the older versions from any matrixes and add some verbiage around the fact that it can run w/ earlier versions but we do not actively test/support them and point to legacy matrix in a wiki (which is this current matrix up to the 1.19 column).

@sabbyanandan one outstanding question though, the 1.23 testing. Did we decide on manually testing this?

[sabbyanandan]

Yeah, let's do it using Minikube/Kind, and we can close it then.

[sabbyanandan]

Something like:

minikube start --memory=8000 --cpus=6 --vm-driver=docker --kubernetes-version v1.23.0