Advanced installation configuration options - Installing OpenShift Serverless | Serverless applications

Knative Serving supported installation configuration options
- Controller Custom Certs
- High availability
Additional resources

This guide provides information for cluster administrators about advanced installation configuration options for OpenShift Serverless components.

Knative Serving supported installation configuration options

This guide provides information for cluster administrators about advanced installation configuration options for Knative Serving.

Do not modify any YAML contained inside the config field. Some of the configuration values in this field are injected by the OpenShift Serverless Operator, and modifying them will cause your deployment to become unsupported.

Create Knative Serving form in web console Administrator Perspective

Controller Custom Certs

If your registry uses a self-signed certificate, you must enable tag-to-digest resolution by creating a ConfigMap or Secret. The OpenShift Serverless Operator then automatically configures Knative Serving controller access to the registry.

To enable tag-to-digest resolution, the Knative Serving controller requires access to the container registry.

The ConfigMap or Secret must reside in the same namespace as the Knative Serving CustomResourceDefinition (CRD).

The following example triggers the OpenShift Serverless Operator to:

Create and mount a volume containing the certificate in the controller.
Set the required environment variable properly.

Example YAML

apiVersion: operator.knative.dev/v1alpha1
kind: KnativeServing
metadata:
  name: knative-serving
  namespace: knative-serving
spec:
  controller-custom-certs:
    name: certs
    type: ConfigMap

The following example uses a certificate in a ConfigMap named certs in the knative-serving namespace.

The supported types are ConfigMap and Secret.

If no controller custom cert is specified, this defaults to the config-service-ca ConfigMap.

Example default YAML

spec:
  controller-custom-certs:
    name: config-service-ca
    type: ConfigMap

High availability

High availability (HA) defaults to 2 replicas per controller if no number of replicas is specified.

You can set this to 1 to disable HA, or add more replicas by setting a higher integer.

Example YAML

spec:
  high-availability:
    replicas: 2

Additional resources

For more information about configuring high availability, see High availability on OpenShift Serverless.