Chapter 10. Tuning eventing configuration

Procedure

1. To change templates for generating consumer group IDs and topic names used by your triggers, brokers, and channels, change the KnativeKafka resource:

   apiVersion: v1
   kind: KnativeKafka
   metadata:
     name: knative-kafka
     namespace: knative-eventing
   # ...
   spec:
     config:
       config-kafka-features:
         triggers.consumergroup.template: <template>
         brokers.topic.template: <template>
         channels.topic.template: <template>

   • triggers.consumergroup.template: The template for generating the consumer group ID used by your triggers. Use a valid Go text/template value. Defaults to "knative-trigger-{{ .Namespace }}-{{ .Name }}".
   • brokers.topic.template: The template for generating Kafka topic names used by your brokers. Use a valid Go text/template value. Defaults to "knative-broker-{{ .Namespace }}-{{ .Name }}".
   • channels.topic.template: The template for generating Kafka topic names used by your channels. Use a valid Go text/template value. Defaults to "messaging-kafka.{{ .Namespace }}.{{ .Name }}".

   The following example displayes template configuration:

   apiVersion: v1
   kind: KnativeKafka
   metadata:
     name: knative-kafka
     namespace: knative-eventing
   # ...
   spec:
     config:
       config-kafka-features:
         triggers.consumergroup.template: "{% raw %}"knative-trigger-{{ .Namespace }}-{{ .Name }}-{{ .annotations.my-annotation }}"{% endraw %}"
         brokers.topic.template: "{% raw %}"knative-broker-{{ .Namespace }}-{{ .Name }}-{{ .annotations.my-annotation }}"{% endraw %}"
         channels.topic.template: "{% raw %}"messaging-kafka.{{ .Namespace }}.{{ .Name }}-{{ .annotations.my-annotation }}"{% endraw %}"

2. Apply the KnativeKafka YAML file by running the following command:

   $ oc apply -f <knative_kafka_filename>

Procedure

1. In the OpenShift Container Platform web console, navigate to OperatorHub Installed Operators.
2. Select the knative-eventing namespace.
3. Click Knative Eventing in the list of Provided APIs for the OpenShift Serverless Operator to go to the Knative Eventing tab.
4. Click knative-eventing, then go to the YAML tab in the knative-eventing page.

5. Change the number of replicas in the KnativeEventing CR:

   You get an output similar to the following example:

   apiVersion: operator.knative.dev/v1beta1
   kind: KnativeEventing
   metadata:
     name: knative-eventing
     namespace: knative-eventing
   spec:
     high-availability:
       replicas: 3

6. You can also specify the number of replicas for a specific workload.

   Note

   Workload-specific configuration overrides the global setting for Knative Eventing.

   You get an output similar to the following example:

   apiVersion: operator.knative.dev/v1beta1
   kind: KnativeEventing
   metadata:
     name: knative-eventing
     namespace: knative-eventing
   spec:
     high-availability:
       replicas: 3
     workloads:
     - name: mt-broker-filter
       replicas: 3

7. Verify that the deployment respects the high availability limits:

   You get an output similar to the following example command:

   $ oc get hpa -n knative-eventing

   You get an output similar to the following example:

   NAME                 REFERENCE                      TARGETS   MINPODS   MAXPODS   REPLICAS   AGE
   broker-filter-hpa    Deployment/mt-broker-filter    1%/70%    3         12        3          112s
   broker-ingress-hpa   Deployment/mt-broker-ingress   1%/70%    3         12        3          112s
   eventing-webhook     Deployment/eventing-webhook    4%/100%   3         7         3          115s

Procedure

1. In the OpenShift Container Platform web console, navigate to OperatorHub Installed Operators.
2. Select the knative-eventing namespace.
3. Click Knative Kafka in the list of Provided APIs for the OpenShift Serverless Operator to go to the Knative Kafka tab.
4. Click knative-kafka, then go to the YAML tab in the knative-kafka page.

5. Change the number of replicas in the KnativeKafka CR:

   You get an output similar to the following example:

   apiVersion: operator.serverless.openshift.io/v1alpha1
   kind: KnativeKafka
   metadata:
     name: knative-kafka
     namespace: knative-eventing
   spec:
     high-availability:
       replicas: 3