重新创建K8s集群并按照上面的cert-manager页面中的步骤进行操作。我犯的一个主要错误是在Ingress中引用了错误的命名空间。

请注意使用cert-manager.io/cluster-issuer

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  annotations:
    # add an annotation indicating the issuer to use.
    cert-manager.io/cluster-issuer: letsencrypt-prod

还请注意，使用cert-manager v11时，apiVersion和求解器会略有不同。

apiVersion: cert-manager.io/v1alpha2
kind: ClusterIssuer
metadata:
  name: letsencrypt-prod
spec:
  acme:
    # You must replace this email address with your own.
    # Let's Encrypt will use this to contact you about expiring
    # certificates,and issues related to your account.
    email: youremail@domain.com
    server: https://acme-v02.api.letsencrypt.org/directory
    privateKeySecretRef:
      # Secret resource used to store the account's private key.
      name: letsencrypt-prod
    # Add a single challenge solver,HTTP01 using nginx
    solvers:
    - http01:
        ingress:
          class: nginx

最后，值得注意的是，Lets-encrypt需要指向有效页面才能提供证书。确保正确指向您的域，并且该域的根目录下有一个页面。产品上有一个速率限制器，因此最好与分段发行者合作，直到提供证书为止。如果运行以下代码，则应显示CertificateCreated。

kubectl describe ingress