Failed to deploy jiva mode by referring to openebs document

[lixiaopengy]

服务版本
openebs：v2.12
kubernetes： v1.18
Reference link：https://openebs.io/docs/user-guides/jiva-guide#create-a-pool

I participated in the above link to learn how to deploy jiva mode, and deployed pool and SC according to the document. However, when the service is used, it shows that PVC cannot be bound

The jiva operator log is not swiped and an error is reported

Error reported in the busybox service log deployed with reference to the document:

Events:
  Type     Reason            Age        From               Message
  ----     ------            ----       ----               -------
  Warning  FailedScheduling  <unknown>  default-scheduler  running "VolumeBinding" filter plugin for pod "busybox-78c496c547-4k5v6": pod has unbound immediate PersistentVolumeClaims
  Warning  FailedScheduling  <unknown>  default-scheduler  running "VolumeBinding" filter plugin for pod "busybox-78c496c547-4k5v6": pod has unbound immediate PersistentVolumeClaims

SC configuration：

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: openebs-jiva-3repl
  annotations:
    openebs.io/cas-type: jiva
    cas.openebs.io/config: |
      - name: ReplicaCount
        value: "3"
      - name: StoragePool
        value: jivapool
provisioner: openebs.io/provisioner-iscsi

Pool configuration and mounted disks：

apiVersion: openebs.io/v1alpha1
kind: StoragePool
metadata:
  name: jivapool
  type: hostdir
spec:
  path: "/home/openebs-jiva"
[root@k8s1 ~]# df -hT | grep /dev/sdb
/dev/sdb                ext4       20G   45M   19G    1% /home/openebs-jiva