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.

Prerequisites

You must have:

• A Kubernetes cluster of a supported version with internet connectivity
• Installed kubectl

You should also:

• Be a cluster admin
• Have access to your DNS provider.
• Have an AWS account so that you can access Route 53 and IAM

Step 1: Add cert-manager to your Kubernetes cluster

1. Install cert-manager:

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

2. Check that cert-manager installs correctly by running

   kubectl get CustomResourceDefinition | grep cert-manager
   

   You should see certificates, certificate requests, challenges, cluster issuers, issuers, and orders.

3. Next, check that your services are running in the cert-manager namespace

   kubectl get all -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: Delegate your domain names and set up DNS01 challenges

Because Coder dynamically generates domains (specifically the dev URLs), your certificates need to be approved and challenged. The following steps will show you how to use Route 53 for DNS01 challenges.

If your domain name is managed by Route 53, the hosted zone will already exist so skip to step 3.

1. Log in to AWS Route 53. On the Dashboard, click Hosted Zone.

2. Click Create Hosted Zone. In the configuration screen, provide the Domain name that you'll use for Coder (e.g., coder.exampleCo.com) and make sure that you've selected Public hosted zone. Click Create hosted zone to proceed.

   When your list of hosted zones refreshes, you'll see that your new records includes multiple values under Value/Route traffic to.

3. Log in to your DNS provider so that you can edit your NS records.

4. Edit your NS record to delegate your zones to AWS by sending each of the values under Value/Route traffic to to your domain name (i.e., delegate ns-X.awsdns-32.net to coder.exampleCo.com).

Step 3: Create an IAM role for clusterIssuer

To make sure that your clusterIssuer can change your DNS settings, create the required IAM role

When you create the secret for cert-manager, referenced below as route53-credentials be sure it is in the cert-manager namespace since it's used by the cert-manager pod to perform DNS configuration changes.

Step 4: Create the ACME Issuer

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 IAM role:

   apiVersion: cert-manager.io/v1
   kind: ClusterIssuer
   metadata:
     name: letsencrypt
   spec:
     acme:
       email: [email protected]
       preferredChain: ""
       privateKeySecretRef:
         name: example-issuer-account-key
       server: https://acme-v02.api.letsencrypt.org/directory
       solvers:
         - dns01:
             route53:
               accessKeyID: your-access-key-ID #secret with IAM Role
               region: your-region
               secretAccessKeySecretRef:
                 key: secret-access-key
                 name: route53-credentials
           selector:
             dnsZones:
               - yourDomain.com
   

   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="*.coder.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 hostSecretName and devurlsHostSecretName are arbitrary strings that you should set to some value that does not conflict with any other secrets in the Coder namespace.

There are also a few additional steps to make sure that your hostname and dev URLs work.

1. Check the contents of your namespace:

   kubectl get all -n <your_namespace> -o wide
   

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

2. Return to Route53 and go to Hosted Zone.

3. Create a new record for your hostname; provide coder as the record name and paste the external IP as the value. Save.

4. Create another record for your dev URLs: set it to *.dev.exampleCo or similar and use the same external IP as the previous step for value. Save.

At this point, you can return to step 6 of the installation guide to obtain the admin credentials you need to log in. If you are not getting a valid certificate after redeploying, see cert-manager's troubleshooting guide for additional assistance.