(Legacy) Renew certificates for a runtime

This documentation is for the legacy Konnect environment at konnect.konghq.com. For the cloud.konghq.com environment, see the current Konnect documentation.

Runtime certificates generated by Konnect Cloud expire every six (6) months.

Renew your certificates to prevent any interruption in communication between Konnect Cloud and any configured runtimes (data planes). If a certificate expires and is not replaced:

The runtime stops receiving configuration updates from the control plane.
The runtime stops sending Vitals and usage data to the control plane.
Each disconnected runtime uses cached configuration to continue proxying and routing traffic.

Depending on your setup, renewing certificates might mean bringing up a new data plane, or generating new certificates and updating data planes with the new files.

Quick setup

If you originally created your data plane container using the quick setup Docker script, we recommend running the script again to create a new data plane with renewed certificates.

Stop the data plane container.
Open Runtime Manager and click Configure New Runtime.
Run the script again to create a new data plane with updated certificates.
Remove the old data plane container.

Advanced setup

If your data planes are running on Linux or Kubernetes, or if you have a Docker data plane container that was not created using the quick setup script, generate new certificates and replace them on the existing nodes.

Generate new certificates

Open Runtime Manager and click Configure New Runtime.
Open the tab that suits your environment: Linux or Kubernetes.

If you’re running a Docker container, you can use either of these tabs to complete the following steps.
Click Generate Certificate.
Save the new certificates and key into separate files:
- Certificate: tls.crt
- Private key: tls.key
- Root CA Certificate: ca.crt
Store the files on your runtime’s local filesystem.

Update data plane

Linux

Kubernetes

Docker

Open your instance’s kong.conf file. Replace existing certificates with the new files:

cluster_cert = /{PATH_TO_FILE}/tls.crt
cluster_cert_key = /{PATH_TO_FILE}/tls.key
lua_ssl_trusted_certificate = system,/{PATH_TO_FILE}
/ca.crt

Restart Kong Gateway for the settings to take effect:

kong restart

Clean up by deleting any old certificate and key files on your filesystem.

Create new secrets for the certificates and key, making sure to name them something different from your current secret names.

Create a tls secret using the tls.cert and tls.key files you saved earlier:

kubectl create secret tls kong-cluster-cert2 -n kong \
   --cert=/{PATH_TO_FILE}/tls.crt \
   --key=/{PATH_TO_FILE}
/tls.key

Create a generic secret for the ca.crt file:

kubectl create secret generic kong-cluster-ca2 -n kong \
   --from-file=ca.crt=/{PATH_TO_FILE}
/ca.crt

Open the values.yaml file for your data plane and update it to point to the new secrets.

Update the secretVolumes section:

 secretVolumes:
 - kong-cluster-cert2
 - kong-cluster-ca2

Update the cert values in the env section:

 env:
   cluster_ca_cert: /etc/secrets/kong-cluster-ca2/ca.crt
   cluster_cert: /etc/secrets/kong-cluster-cert2/tls.crt
   cluster_cert_key: /etc/secrets/kong-cluster-cert2/tls.key
   lua_ssl_trusted_certificate: /etc/secrets/kong-cluster-ca2/ca.crt

Save the file. Reapply the configuration by running the Helm upgrade command:

 helm upgrade my-kong kong/kong -n kong \
   --values ./values.yaml

Delete the old secrets.

The kong-cluster-cert secret:

 kubectl delete secret kong-cluster-cert

And the kong-cluster-ca secret:

 kubectl delete secret kong-cluster-ca

In your Docker container, replace existing certificates on your data planes with the new files and restart the Gateway:

echo "KONG_CLUSTER_CERT=/{PATH_TO_FILE}/tls.crt \
  KONG_CLUSTER_CERT_KEY=/{PATH_TO_FILE}/tls.key \
  KONG_LUA_SSL_TRUSTED_CERTIFICATE=/{PATH_TO_FILE}/ca.crt \
  kong reload exit" | docker exec -i {KONG_CONTAINER_ID}
 /bin/sh

Clean up by deleting any old certificate and key files on your filesystem.