Kubectl GKE PersistentVolumeClaim - kubernetes

Question

Folks, when running the following kubectl command:
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
name: openvpn-data-claim
namespace: openvpn
spec:
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
error: SchemaError(io.k8s.api.autoscaling.v1.Scale): invalid object doesn't have additional properties
kubectl version
Client Version: version.Info{Major:"1", Minor:"10", GitVersion:"v1.10.11", GitCommit:"637c7e288581ee40ab4ca210618a89a555b6e7e9", GitTreeState:"clean", BuildDate:"2018-11-26T14:38:32Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"15+", GitVersion:"v1.15.9-gke.24", GitCommit:"39e41a8d6b7221b901a95d3af358dea6994b4a40", GitTreeState:"clean", BuildDate:"2020-02-29T01:24:35Z", GoVersion:"go1.12.12b4", Compiler:"gc", Platform:"linux/amd64"}

Answer 1

This answer is is an addition to #Cmag answer and
my intention is to provide more insights about this issue to help the community.
According to Kubernetes Version Skew Policy:
kubectl is supported within one minor version (older or newer) of kube-apiserver.
IF kube-apiserver is at 1.15: kubectl is supported at 1.16, 1.15, and 1.14.
Note: If version skew exists between kube-apiserver instances in an HA cluster, for example kube-apiserver instances are at 1.15 and 1.14, kubectl will support only 1.15 and 1.14 since any other versions would be more than one minor version skewed.
Each update of kubernetes has many components that are added, changed, moved, deprecated or removed. Here is the Kubernetes Changelog of version 1.15.
Even running a much newer client versions may give you some issues
In K8s 1.10 the kubectl run had a default behavior of creating deployments:
❯ ./kubectl-110 run ubuntu --image=ubuntu
deployment.apps "ubuntu" created
Starting on 1.12 the kubectl run was deprecated to all generators except pods, here is an example with kubectl 1.16:
❯ ./kubectl-116 run ubuntu --image=ubuntu --dry-run
kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
deployment.apps/ubuntu created (dry run)
Besides the warning, it still work as intended, but it changed in K8s 1.18 client:
❯ ./kubectl-118 version
Client Version: version.Info{Major:"1", Minor:"18", GitVersion:"v1.18.2", GitCommit:"52c56ce7a8272c798dbc29846288d7cd9fbae032", GitTreeState:"clean", BuildDate:"2020-04-16T11:56:40Z", GoVersion:"go1.13.9", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"15+", GitVersion:"v1.15.9-gke.24", GitCommit:"39e41a8d6b7221b901a95d3af358dea6994b4a40", GitTreeState:"clean", BuildDate:"2020-02-29T01:24:35Z", GoVersion:"go1.12.12b4", Compiler:"gc", Platform:"linux/amd64"}
$ kubectl run --generator=deployment/apps.v1 ubuntu --image=ubuntu --dry-run=client
Flag --generator has been deprecated, has no effect and will be removed in the future.
pod/ubuntu created (dry run)
It ignored the flag and created only a pod. That flag is supported by kubernetes 1.15 as we saw in the test, but the kubectl 1.18 had significant changes that did not allowed running it.
This is a simple example to illustrate the importance to follow the skew policy on Kubernetes, it can save a lot of troubleshooting time in the future!

Answer 2

Easily fixed by upgrading local kubectl with asdf.
asdf install kubectl 1.15.9