Obtain TLS certificates: An example

This topic is intended as an example only. It explains how to obtain a TLS certificate from the certificate authority (CA) Let's Encrypt. These steps are provided primarily as an example to follow if you do not have another ready way to obtain a certificate/key pair that is authorized by a CA. The example shows how to generate certificates using the Let's Encrypt CA, the Certbot client, and Google Cloud Platform Cloud DNS.

Where you can use these certificates

You must provide TLS certificates for two Istio ingress gateways that are exposed outside the cluster:

Gateway TLS requirement
Runtime ingress gateway You can use a self-signed certificate/key pair or authorized TLS certificates.
MART ingress gateway (optional when not using Apigee Connect) Requires an authorized TLS certificate/key pair or Kubernetes secret.
See also External connections.

Requirements

You will need a domain name obtained through a domain name registrar. You can register a domain name through Google Domains or another domain registrar of your choice.

Configure Cloud DNS

To obtain authorized TLS certificates, you must have a qualified domain name. The following steps explain how to use Google Cloud DNS to obtain a domain name and manage your domain servers.
  1. Open the Google Cloud console and log in with the account you created in Step 1: Create a Google Cloud account.
  2. Select the project that you created in Step 2: Create a GCP project.
  3. If you have not already done so, enable the Cloud DNS API. See Enabling APIs.
  4. Create a static IP address:
    • If you are on GKE, follow the instructions in Reserving a static external IP address to create a static IP addresses that external processes can use to communicate with the hybrid runtime ingress. You can give the address any name you wish, for example: apigee-hybrid-runtime. When you finish, you will use the IP number in the cluster configuration in the next step. For example: 34.66.75.196
    • If you are on Anthos GKE, follow instructions in the Anthos GKE documentation to create a static IP address.
  5. Get the External IP you just reserved.
  6. Create record set for the runtime Istio ingress endpoint. This is the address for making API calls to the hybrid gateway. Enter the External IP you obtained in the previous step and add a prefix to the domain name, such as example-endpoint. For instructions, see Create a new record.
    1. Create a managed public zone. For instructions, see Create a managed public zone.
    2. Create a new record set with:
      • DNS Name: The name of the endpoint external API calls will communicate with, like api-services or example-endpoint
      • Resource Record Type: A
      • TTL and TTL Unit: Accept defaults
      • IP Adddress: The static IP you created.
  7. The Zone details view will list foour DNS servers as the NS data for your new zone. Copy the DNS record data, as shown in the following example:

  8. Return to your domain page at your registrar (for example, Google Domains).
  9. Select your domain.
  10. Select DNS.
  11. In the Name Servers section, click Edit.
  12. Enter the domain name servers that you copied from the Network Services Cloud DNS page. For example:

Now, your Google Cloud DNS will manage the DNS records for your domain.

Install Certbot on a VM

Now that you have Cloud DNS set up to manage your domain servers, you will install the Certbot client with the dns_google plugin on a Cloud VM. The client enables you to get authorized certificates for your domain from a Let's Encrypt endpoint.

  1. Open the Google Cloud console and log in with the account you created in Step 1: Create a Google Cloud account.
  2. Select the project that you created in Step 2: Create a GCP project.
  3. Select IAM & admin > Service accounts.

    The Service accounts view displays a list of the project’s service accounts.

  4. To create a new service account, click +Create Service Account at the top of the view.

    The Service account details view displays.

  5. In the Service account name field, enter the name of the service account.

    You can optionally add a description in the Service account description field. Descriptions are helpful at reminding you what a particular service account is used for.

  6. Click Create.

    GCP creates a new service account and displays the Service account permissions view. Use this view to assign a role to your new service account.

  7. Click the Select a role drop-down list.
  8. Select the Project Owner role.
  9. Click Continue.
  10. Click Done.
  11. In the GCP console, select Compute Engine > VM Instances.
  12. Create a VM instance named certmanager.
  13. Under the Boot Disk section, choose CentOS7 and 20 GB for the SSD persistent drive.
  14. Set the Service Account to the one you created above.
  15. Install Certbot and the dns_google plugin on the machine and run the Certbot client:
      sudo su -
      yum -y install yum-utils
      yum install certbot -y
      yum install certbot-dns-google -y
      certbot certonly --dns-google -d *.your_domain_name,*.your_domain_name --server https://acme-v02.api.letsencrypt.org/directory
      

    For example:

    sudo su -
    yum -y install yum-utils
    yum install certbot -y
    yum install certbot-dns-google -y
    certbot certonly --dns-google -d *.apigee-hybrid-docs.net,*.apigee-hybrid-docs.net --server https://acme-v02.api.letsencrypt.org/directory
    
  16. You can now find your authorized certificate and private key files in this directory: cd /etc/letsencrypt/live/your_domain_name/

    For example:

    cd /etc/letsencrypt/live/apigee-hybrid-docs.net
    ls
      cert.pem  chain.pem  fullchain.pem  privkey.pem  README
  17. Copy the files fullchain.pem and privkey.pem to your local machine.
  18. Optional: Create a Kubernetes secret with the certificate/key pair. See the instructions in Option 2: Kubernetes Secret in Configuring TLS and mTLS on the Istio ingress.
  19. Update your overrides file to point to the certificate and private key. For the hostAliases, use the DNS name that you created previously.

    For example:

    ...
    envs:
      - name: test
        serviceAccountPaths:
          synchronizer: "your_keypath/synchronizer-manager-service-account.json
          udca: "your_keypath/analytic-agent-service-account.json
    
    virtualhosts:
      - name: my-env-group
        sslCertPath: "$HOME/hybrid/apigee-hybrid-setup/tls/fullchain.pem"
        sslKeyPath: "$HOME/hybrid/apigee-hybrid-setup/tls/privkey.pem"
    
    mart: # Assuming you are not using Apigee Connect
      nodeSelector:
        key: cloud.google.com/gke-nodepool
        value: apigee-runtime
      sslCertPath: "$HOME/hybrid/apigee-hybrid-setup/tls/fullchain.pem"
      sslKeyPath: "$HOME/hybrid/apigee-hybrid-setup/tls/privkey.pem"
      replicaCountMin: 1
      replicaCountMax: 1

    Or if using Kubernetes secrets:

    ...
    envs:
      - name: test
        serviceAccountPaths:
          synchronizer: "your_keypath/synchronizer-manager-service-account.json
          udca: "your_keypath/analytic-agent-service-account.json
    
    virtualhosts:
      - name: my-env-group
        tlsMode: SIMPLE  # Note: SIMPLE is the default, MUTUAL is also an available value.
        sslSecret: myorg-test-policy-secret"
    
    mart: # Assuming you are not using Apigee Connect
      nodeSelector:
        key: cloud.google.com/gke-nodepool
        value: apigee-runtime
        sslSecret: myorg-test-policy-secret"
      replicaCountMin: 1
      replicaCountMax: 1
    
    ...  
  20. Apply the changes:

    If you changed the mart configuration, apply the changes:

    apigeectl apply -f your_overrides_file --all-envs

    If you changed the envs configuration, apply the changes:

    apigeectl apply -f your_overrides_file --all-envs
  21. Test the configuration

    Deploy and test a proxy, as explained in Create and deploy a new API proxy.