Wildcard Let's Encrypt certificates with cert-manager, nginx ingress, cloudflare in kubernetes how to fix?

Question

I have Cloudflare DNS for manage my domain. I created an A-record *.play.mydomain.com in Cloudflare.

In Kubernetes (GKE) I created Issuer

apiVersion: certmanager.k8s.io/v1alpha1
kind: Issuer
metadata:
  name: letsencrypt-prod-wildcard
  namespace: default
spec:
  acme:
    server: https://acme-staging-v02.api.letsencrypt.org/directory
    #server: https://acme-v02.api.letsencrypt.org/directory
    email: myemain@gmail.com

    # Name of a secret used to store the ACME account private key
    privateKeySecretRef:
      name: letsencrypt-prod-wildcard

    # ACME DNS-01 provider configurations
    dns01:

    challenges
      providers:
        - name: cf-dns
          cloudflare:
            email: myimail@gmail.com
            # A secretKeyRef to a cloudflare api key
            apiKeySecretRef:
              name: cloudflare-api-key
              key: api-key.txt

And I created secrets for cloudflare (cloudflare-api-key)

Also I created wildcard-certificate:

apiVersion: certmanager.k8s.io/v1alpha1
kind: Certificate
metadata:
  name: wildcard-mydomain-com
  namespace: default
spec:
  secretName: wildcard-mydomain-com
  issuerRef:
    #name: letsencrypt-staging-wildcard
    name: letsencrypt-prod-wildcard
  commonName: '*.play.mydomain.com'
  dnsNames:
  - play.mydomain.com
  acme:
    config:
    - dns01:
        provider: cf-dns
      domains:
      - '*.play.mydomain.com'
      - play.mydomain.com

Certificate generated successfully.

Status:
  Conditions:
    Last Transition Time:  2019-04-13T00:49:00Z
    Message:               Certificate is up to date and has not expired
    Reason:                Ready
    Status:                True
    Type:                  Ready
  Not After:               2019-07-11T23:48:57Z
Events:
  Type    Reason              Age   From          Message
  ----    ------              ----  ----          -------
  Normal  Generated           4m5s  cert-manager  Generated new private key
  Normal  GenerateSelfSigned  4m5s  cert-manager  Generated temporary self signed certificate
  Normal  OrderCreated        4m5s  cert-manager  Created Order resource "wildcard-mydomain-com-880037411"
  Normal  OrderComplete       84s   cert-manager  Order "wildcard-mydomain-com-880037411" completed successfully
  Normal  CertIssued          84s   cert-manager  Certificate issued successfully

But in logs cert-manager I see an error:

2019-04-13 04:49:00.078 GET
orders controller: Re-queuing item "default/wildcard-mydomain-com-880037411" due to error processing: challenges.certmanager.k8s.io "wildcard-mydomain-com-880037411-1" not found

Also I have an ingress:

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: ingress-mydomain-com
  annotations:
    kubernetes.io/ingress.class: nginx
    certmanager.k8s.io/issuer: letsencrypt-prod-wildcard
    certmanager.k8s.io/acme-challenge-type: "dns01"
    kubernetes.io/tls-acme: "true"

spec:
  tls:
  - secretName: letsencrypt-prod-secret-playground
    hosts:
      - '*.play.mydomain.com'

  rules:
  - host: '*.play.mydomain.com'
    http:
      paths:
      - backend:
          serviceName: playground
          servicePort: 83

And an error in logs (after run ingress):

2019-04-13 04:51:17.225 GET
orders controller: Re-queuing item "default/letsencrypt-prod-secret-playground-2579012660" due to error processing: Error constructing Challenge resource for Authorization: ACME server does not allow selected challenge type or no provider is configured for domain "play.mydomain.com"

How I can use wildcard certificates Let's Encrypt with cert-manager, nginx ingress, cloudflare in kubernetes?

I'd like to have ingress and launch many subdomains ([randomstring].play.mydomain.com).

Answer 1

Note : might require to first add the CAA record in DNS.

CAA record can get added into DNS zone

example :

            Type       Value

devops.in   CAA       0 issuewild "letsencrypt.org"

secret storing access key

kubectl create secret generic route53-secret --from-literal=secret-access-key="skjdflk4598sf/dkfj490jdfg/dlfjk59lkj"

Here sharing the example issuer.yaml

apiVersion: cert-manager.io/v1
kind: Issuer
metadata:
  name: letsencrypt-prod
spec:
  acme:
    email: test123@gmail.com
    server: https://acme-v02.api.letsencrypt.org/directory
    privateKeySecretRef:
      name: letsencrypt-prod
    solvers:
    - selector:
        dnsZones:
          - "devops.in"
      dns01:
        route53:
          region: us-east-1
          hostedZoneID: Z2152140EXAMPLE
          accessKeyID: AKIA5A5D7EXAMPLE
          secretAccessKeySecretRef:
            name: route53-secret
            key: secret-access-key
---
apiVersion: cert-manager.io/v1alpha2
kind: Certificate
metadata:
  name: le-crt
spec:
  secretName: tls-secret
  issuerRef: 
    kind: Issuer
    name: letsencrypt-prod
  commonName: "*.devops.in"
  dnsNames:
    - "*.devops.in" 

Answer 2

It looks mostly correct a couple of issues I see

1. challenges keyword seems out of place in the Issuer. Maybe it was on purpose to explain(?)

   # ACME DNS-01 provider configurations
   dns01:
     providers:
     - name: cf-dns
       cloudflare:
         email: myimail@gmail.com
         # A secretKeyRef to a cloudflare api key
         apiKeySecretRef:
           name: cloudflare-api-key
           key: api-key.txt
   

2. Missing kind: Issuer line within the issuerRef in your Certificate definition and dnsNames shows play.mydomain.com instead of *.play.mydomain.com (which could be the problem)

   apiVersion: certmanager.k8s.io/v1alpha1
   kind: Certificate
   metadata:
     name: wildcard-mydomain-com
     namespace: default
   spec:
     secretName: wildcard-mydomain-com
     issuerRef:
       name: letsencrypt-prod-wildcard
       kind: Issuer
     commonName: '*.play.mydomain.com'
     dnsNames:
     - *.play.mydomain.com <== here
     acme:
       config:
       - dns01:
           provider: cf-dns
         domains:
         - '*.play.mydomain.com'
         - play.mydomain.com