This guide will show you how to install cert-manager v1.0.1 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.
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:
# Kubernetes 1.16+ $ kubectl apply --validate=false -f \ https://github.com/jetstack/cert-manager/releases/download/v1.0.1/cert-manager.yaml # Kubernetes <1.16 $ kubectl apply --validate=false -f \ https://github.com/jetstack/cert-manager/releases/download/v1.0.1/cert-manager-legacy.yaml
--validate=falseis required to bypass kubectl's resource validation on the client-side that exists in older versions of Kubernetes.
Once you've started the installation process, you can 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
cert-manager supports HTTP01 and DNS01 challenges, as well as many DNS providers. This guide, however, shows you how to use Cloudflare for DNS01 challenges. This is necessary to issue wildcard certificates, which are required for Coder's Dev URLs feature.
First, get the Cloudflare API credentials for cert-manager to use; cert-manager needs permission to add a temporary TXT record and delete it after the challenge has been completed.
Open the Cloudflare dashboard and go to My Profile > API Tokens. Click Create Token, then go to Create Custom Token and click Get Started.
Create a token with the following settings:
You can also add more zones (or give the token access to all zones in your account), and set an expiry date.
Click Continue to summary, then Create Token. Be sure to copy and save the token displayed because Cloudflare will not display it again.
Now that we have our Cloudflare API token, we need to configure cert-manager to use it. In a text editor, create a new file called issuer.yaml and paste the following:
apiVersion: v1 kind: Secret metadata: name: cloudflare-api-key-secret namespace: coder # Your Coder deployment namespace type: Opaque stringData: api-key: "" # Your Cloudflare API token (from earlier) apiVersion: cert-manager.io/v1alpha2 kind: Issuer metadata: name: letsencrypt namespace: coder # Your Coder deployment namespace spec: acme: email: "" # Your email address (given to Let's Encrypt) server: "https://acme-v02.api.letsencrypt.org/directory" privateKeySecretRef: name: letsencrypt-account-key solvers: - dns01: cloudflare: email: "" # Your Cloudflare email address apiTokenSecretRef: name: cloudflare-api-key-secret key: api-key # This section denotes which domains to use this issuer for. If you didn't # limit which zones the API token had access to, you may wish to remove # this section. selector: dnsZones: # Only use this issuer for the domain example.com and its subdomains. - 'example.com'
cert-manager has a concept of Issuer (which are per-namespace) or ClusterIssuer (which are global to the entire cluster). If you plan on using cert-manager only for Coder, you may choose to use the Issuer configuration above. If you want to use a ClusterIssuer instead, you'll need to make the following changes:
For further information, see Setting Up Issuers.
Read the comments and fill out the blanks. Once you're done, you can go ahead and apply that to your cluster using:
$ kubectl apply -f issuer.yaml secret/cloudflare-api-key-secret created issuer.cert-manager.io/letsencrypt created
If your installation uses an external egress, you'll need to configure your ingress to use the coder-root-cert and coder-devurls-cert.
However, if you're using the default ingress included in the helm chart, you can use the following helm values to configure the internal ingress and automatically create your certificate:
ingress: useDefault: true host: "coder.example.com" tls: enable: true hostSecretName: coder-root-cert devurlsHostSecretName: coder-devurls-cert additionalAnnotations: - 'cert-manager.io/issuer: letsencrypt' devurls: host: "*.coder.example.com"
Be sure to redeploy Coder after altering your helm values.