cert-manager allows you to enable HTTPS on your Coder installation, regardless of whether you're using Let's Encrypt or you have your own certificate authority.

This guide will show you how to install cert-manager v1.4.0 and set up your cluster to issue Let's Encrypt certificates for your Coder installation so that you can enable HTTPS on your Coder deployment. It will also show you how to configure your Coder hostname and dev URLs.

We recommend reviewing the official cert-manager documentation if you encounter any issues or if you want info on using a different certificate issuer.

You must have:

• A Kubernetes cluster of a supported version with internet connectivity
• Installed kubectl
• A Cloud DNS account
• A GCP Service Account with the dns.admin role

Step 1: Add cert-manager to your Kubernetes cluster

To add cert-manager to your cluster, run:

kubectl apply -f https://github.com/jetstack/cert-manager/releases/download/v1.4.0/cert-manager.yaml

More specifics can be found in the cert-manager install documentation.

Once you've started the installation process, verify that all the pods are running:

$ kubectl get pods -n cert-manager

NAME                                       READY   STATUS    RESTARTS   AGE
cert-manager-7cd5cdf774-vb2pr              1/1     Running   0          84s
cert-manager-cainjector-6546bf7765-ssxhf   1/1     Running   0          84s
cert-manager-webhook-7f68b65458-zvzn9      1/1     Running   0          84s

Step 2: Get the private key from the service account

You can get the private key from the GCP Service Account using:

gcloud iam service-accounts keys create key.json \
--iam-account <service-account-name>@<project-name>.iam.gserviceaccount.com

The response should look similar to the following:

created key [44...3d] of type [json] as [key.json] for [<service-account-name>@<project-name>.iam.gserviceaccount.com]

Step 3: Configure cluster issuer secret and add it to cert-manager namespace

Next, configure the cluster issuer secret, and add it to cert-manager's namespace:

kubectl -n cert-manager create secret generic \
clouddns-dns01-solver-svc-acct --from-file=./key.json

If successful, you'll see a response similar to:

secret/clouddns-dns01-solver-svc-acct created

Step 4: Create a cluster issuer resource and apply it

1. Using the text editor of your choice, create a new configuration file called letsencrypt.yaml (you can name it whatever you'd like) that includes your newly created private key:

   apiVersion: cert-manager.io/v1
   kind: ClusterIssuer
   metadata:
     name: letsencrypt
   spec:
     acme:
       privateKeySecretRef:
         name: gclouddnsissuersecret
       server: https://acme-v02.api.letsencrypt.org/directory
       solvers:
         - dns01:
             clouddns:
               # The ID of the GCP project
               project: <project-id>
               # This is the secret used to access the service account
               serviceAccountSecretRef:
                 name: clouddns-dns01-solver-svc-acct
                 key: key.json
   

   More information on the values in the YAML file above can be found in the dns01 solver configuration documentation.

2. Apply your configuration changes:

   kubectl apply -f letsencrypt.yaml
   

   If successful, you'll see a response similar to:

   clusterissuer.cert-manager.io/letsencrypt created
   

Step 5: Install Coder

At this point, you're ready to install Coder. However, to use all of the functionality you set up in this tutorial, use the following helm install command instead:

helm install coder coder/coder --namespace coder \
  --version=<CODER_VERSION> \
  --set devurls.host="*.exampleCo.com" \
  --set ingress.host="coder.exampleCo.com" \
  --set ingress.tls.enable=true \
  --set ingress.tls.devurlsHostSecretName="coder-devurls-cert" \
  --set ingress.tls.hostSecretName="coder-root-cert" \
  --set ingress.annotations.cert-manager\.io/cluster-issuer="letsencrypt" \
  --wait

The cluster-issuer will create the certificates you need, using the values provided in the helm install command for the dev URL and host secret.

There are additional steps to make sure that your hostname and Dev URLs work.

Step 6: Configure DNS resolution

1. Check the contents of your namespace

   kubectl get all -n <your_namespace> -o wide
   

   Find the service/ingress-nginx line and copy the external IP value shown.

2. Return to Google Cloud Platform, navigate to the Cloud DNS Console, and select the Zone that your cluster is in.

   Note: You will need to create two A records, one for both the hostname and Dev URLs

3. Click Add Record Set

4. Provide your DNS Name

   a. If you're configuring the hostname, this value will be a standard domain

   b. If you're configuring your dev URLs, this will be a wildcard domain (e.g., *.domain.com)

5. Set the Resource Record Type to A

6. Copy and paste the IP address from the service/ingress-nginx line in your terminal to the IPv4 Address field

7. Click Create

At this point, you can return to step 6 of the installation guide to obtain the admin credentials you need to log in.

Troubleshooting

If you are not getting a valid certificate after redeploying, see cert-manager's troubleshooting guide for additional assistance.