描述
kubernetes v1.20版本创建pvc 报错

E0304 06:18:05.352939       1 controller.go:1004] provision "default/diss-db-pvc" class "managed-nfs-storage": unexpected error getting claim reference: selfLink was empty, can't make reference
I0304 06:18:06.365388       1 controller.go:987] provision "default/diss-db-pvc" class "managed-nfs-storage": started
E0304 06:18:06.371904       1 controller.go:1004] provision "default/diss-db-pvc" class "managed-nfs-storage": unexpected error getting claim reference: selfLink was empty, can't make reference
I0304 06:23:09.410514       1 controller.go:987] provision "default/diss-db-pvc" class "managed-nfs-storage": started
E0304 06:23:09.416387       1 controller.go:1004] provision "default/diss-db-pvc" class "managed-nfs-storage": unexpected error getting claim reference: selfLink was empty, can't make reference
I0304 06:23:16.933814       1 controller.go:987] provision "default/diss-db-pvc" class "managed-nfs-storage": started
E0304 06:23:16.937994       1 controller.go:1004] provision "default/diss-db-pvc" class "managed-nfs-storage": unexpected error getting claim reference: selfLink was empty, can't make reference
I0304 06:33:06.365740       1 controller.go:987] provision "default/diss-db-pvc" class "managed-nfs-storage": started
E0304 06:33:06.369275       1 controller.go:1004] provision "default/diss-db-pvc" class "managed-nfs-storage": unexpected error getting claim reference: selfLink was empty, can't make reference
I0304 06:48:06.365940       1 controller.go:987] provision "default/diss-db-pvc" class "managed-nfs-storage": started
E0304 06:48:06.369685       1 controller.go:1004] provision "default/diss-db-pvc" class "managed-nfs-storage": unexpected error getting claim reference: selfLink was empty, can't make reference
I0304 06:56:41.027826       1 controller.go:987] provision "default/diss-db-pvc" class "managed-nfs-storage": started
E0304 06:56:41.030424       1 controller.go:1004] provision "default/diss-db-pvc" class "managed-nfs-storage": unexpected error getting claim reference: selfLink was empty, can't make reference
I0304 06:56:53.795508       1 controller.go:987] provision "default/diss-db-pvc" class "managed-nfs-storage": started
E0304 06:56:53.803277       1 controller.go:1004] provision "default/diss-db-pvc" class "managed-nfs-storage": unexpected error getting claim reference: selfLink was empty, can't make reference
I0304 07:03:06.366503       1 controller.go:987] provision "default/diss-db-pvc" class "managed-nfs-storage": started
E0304 07:03:06.372021       1 controller.go:1004] provision "default/diss-db-pvc" class "managed-nfs-storage": unexpected error getting claim reference: selfLink was empty, can't make reference

找了找资料发现，kubernetes 1.20版本 禁用了 selfLink。

解决方法
资料连接：
https://stackoverflow.com/questions/65376314/kubernetes-nfs-provider-selflink-was-empty
https://github.com/kubernetes-sigs/nfs-subdir-external-provisioner/issues/25

当前的解决方法是编辑/etc/kubernetes/manifests/kube-apiserver.yaml
在这里：

spec:
  containers:
  - command:
    - kube-apiserver

添加这一行：

- --feature-gates=RemoveSelfLink=false

然后应用它，(我需要运行两次)，即可

kubectl apply -f /etc/kubernetes/manifests/kube-apiserver.yaml

kubectl apply -f /etc/kubernetes/manifests/kube-apiserver.yaml