Renew Certificates for a Data Plane Node

Data plane certificates generated by Kong Konnect expire every ten years. If you bring your own certificates, make sure to review the expiration date and associated metadata.

Renew your certificates to prevent any interruption in communication between Kong Konnect and any configured data plane nodes. The following happens if a certificate expires and isn’t replaced:

The data plane node stops receiving configuration updates from the control plane.
The data plane node stops sending analytics and usage data to the control plane.
Each disconnected data plane node 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 plane nodes with the new files.

Quick setup

If you originally created your data plane node container using one of the Docker options in Gateway Manager, we recommend creating a new data plane node with renewed certificates.

Stop the data plane node container.
Open Gateway Manager, select a control plane, open Data Plane Nodes from the side menu, and click New Data Plane Node.
Run the script to create a new data plane node with updated certificates.
Remove the old data plane node container.

Advanced setup

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

Generate new data plane certificate

Gateway Manager

Konnect API

You can generate a new data plane certificate from the Gateway Manager.

Select a control plane.
Click Actions and select Data plane certificates.
Click Generate certificate.
Save the new certificate and key into separate files:
- certificate: tls.crt
- private key: tls.key
Store the files on the local file system.

You can generate a certificate locally and use the pin data plane client certificate endpoint to add it to Konnect.

Generate a new certificate and key:

openssl req -new -x509 -nodes -newkey rsa:2048 -subj "/CN=kongdp/C=US" -keyout ./tls.key -out ./tls.crt

Reformat the certificate into a single line for the API call:

 export CERT=$(awk 'NF {sub(/\r/, ""); printf "%s\\n",$0;}' tls.crt)

POST the certificate to your control plane using the Konnect API:

 curl https://{region}.api.konghq.com/v2/control-planes/{controlPlaneId}/dp-client-certificates --json '{"cert":"'"$CERT"'"}' \
    --header "Authorization: Bearer ${KONNECT_TOKEN}"

Update data plane

Linux

Kubernetes

Docker

Open your node’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

Restart Kong Gateway for the settings to take effect:

kong restart

Delete 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 the 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

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

Update the secretVolumes section:

 secretVolumes:
 - kong-cluster-cert2

Update the cert values in the env section:

 env:
   cluster_cert: /etc/secrets/kong-cluster-cert2/tls.crt
   cluster_cert_key: /etc/secrets/kong-cluster-cert2/tls.key

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 kong-cluster-cert secret:

 kubectl delete secret kong-cluster-cert

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

docker cp {PATH_TO_FILE}/tls.cert {CONTAINER_ID}:{PATH_TO_FILE}
docker cp {PATH_TO_FILE}/tls.key {CONTAINER_ID}:{PATH_TO_FILE}

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

Delete any old certificate and key files on your filesystem.