Doesn't work on K8s version 1.27 due to out of date KubeSchedulerConfiguration

[adamtwiss]

Bug Report

What version of Kubernetes are you using?
1.27.3

What version of TiDB Operator are you using?
1.5.1

What storage classes exist in the Kubernetes cluster and what are used for PD/TiKV pods?
Rook: ceph-block/ceph-filesystem

What's the status of the TiDB cluster pods?

NAME                                      READY   STATUS             RESTARTS        AGE   IP             NODE         NOMINATED NODE   READINESS GATES
tidb-controller-manager-58f8f675b-6whgc   1/1     Running            0               18h   10.255.0.252   enkubea001   <none>           <none>
tidb-scheduler-7f6d7b4b84-6l6xp           1/2     CrashLoopBackOff   7 (2m50s ago)   13m   10.255.0.74    enkubea001   <none>           <none>

What did you do?
Clean install.

What did you expect to see?
All pods working

What did you see instead?
In logs for: tidb-scheduler-7f6d7b4b84-6l6xp:kube-scheduler
│ E1024 08:52:14.638974 1 run.go:74] "command failed" err="no kind "KubeSchedulerConfiguration" is registered for version "kubescheduler.config.k8s.io/v1beta2" in scheme "pkg/sched │
│ Stream closed EOF for {$namespace}/tidb-scheduler-7f6d7b4b84-6l6xp (kube-scheduler)

The error is because

tidb-operator/charts/tidb-operator/templates/config/_scheduler-config-yaml.tpl

Line 2 in 91fbecb

apiVersion: kubescheduler.config.k8s.io/v1beta2

creates:
kubescheduler.config.k8s.io/v1beta2 which is now deprecated. The fix is to use just kubescheduler.config.k8s.io/v1 which has been about some time.
beta2 was deprecated in kubernetes1.25, when v1 was released (https://sysdig.com/blog/kubernetes-1-25-whats-new/)

The fix is probably another "if semverCompare" where for version 1.25 or later use v1 of the API.

[csuzhangxc]

@adamtwiss Thanks for your report. We're planning to upgrade the K8s deps to v1.25.

[csuzhangxc]

BTW, there is no need to use tidb-scheduler after K8s v1.19, ref https://docs.pingcap.com/tidb-in-kubernetes/stable/tidb-scheduler