kubernetes 证书不适用于让我们加密证书管理器

Question

我似乎无法让证书管理器工作：

$ kubectl get certificates -o wide
NAME         READY   SECRET       ISSUER        STATUS                                         AGE
tls-secret   False   tls-secret   letsencrypt   Issuing certificate as Secret does not exist   115m

$ kubectl get CertificateRequest -o wide
NAME               READY   ISSUER        STATUS                                                                                        AGE
tls-secret-xxxx   False   letsencrypt   Referenced "ClusterIssuer" not found: clusterissuer.cert-manager.io "letsencrypt" not found   113m

我的certificate.yaml是：

apiVersion: cert-manager.io/v1alpha2
kind: Certificate
metadata:
  name: tls-secret
  namespace: default
spec:
  secretName: tls-secret
  dnsNames:
  - aks-xxxx.xxxxx.xxxx.aksapp.io
  acme:
    config:
    - http01:
        ingress:
          name: xxxxxx
      domains:
      - aks-xxxx.xxxxx.xxxx.aksapp.io
  issuerRef:
    name: letsencrypt-staging
    kind: ClusterIssuer

当我获得集群发行者时

  $ kubectl get clusterissuers
    No resources found

知道出了什么问题吗？