lab-15

Lab 15 - Strimzi 0.19 + 0.20 / AMQ Streams 1.6.0

Install cluster operator

• Create namespace/project myproject and set it as default.
• On Openshift
  • oc new-project myproject
  • oc project myproject
• On Kubernetes
  • kubectl create ns myproject
  • kubectl config set-context --current --namespace=myproject

On OCP4 and OCP 3.11

• Install the operator using Operator Hub (as namespaces into the myproject namespace)
• Or install the operator from YAML files:
  • kubectl apply -f amq-streams-1.6.0/

On Kubernetes

• Install the operator from OperatorHub.io
• Or install the operator from YAML files:
  • kubectl apply -f strimzi-0.20.0/

New Listener configuration

• Deploy Kafka with an old listener configuration

  • kubectl apply -f listeners-old-config.yaml
  • In case you are on Kubernetes, you can use loadbalancer or nodeport listener
  • You can check how the Kafka resource is using the old configuration

• Update the configuration to use the new listeners

  • kubectl apply -f listeners-new-config.yaml or edit it manually
  • There should be no rolling update!
  • Look at the updated YAML and notice the important parts
    • The name and port values are important for backwards compatibility
    • The tls flag is now mandatory
    • Notice it is configured as array

      - name: plain
        port: 9092
        type: internal
        tls: false
        authentication:
          type: scram-sha-512
      - name: tls
        port: 9093
        type: internal
        tls: true
        authentication:
          type: tls
      - name: external
        port: 9094
        type: route
        tls: true
        authentication:
          type: tls

• On your own:

  • See what happens when you change the names or port numbers for the existing external listener and how it affects the service names and addresses
  • See what happens when you change the names or port numbers for the existing plain or tls listener and how it affects the service configuration (port names)

• Try to use some of the new features

  • Add second internal listener with TLS encryption and SCRAM-SHA-512 authentication
  • Add second listener using load balancers (if supported in your environment) or node ports
  • kubectl apply -f listeners-more-listeners.yaml
  • Notice the changes to the YAML

      - name: tls2
        port: 9095
        type: internal
        tls: true
        authentication:
          type: scram-sha-512
      - name: external2
        port: 9096
        type: loadbalancer
        tls: true
        authentication:
          type: tls

Dynamic logging changes

Cluster Operator logging

• Check out the ConfigMap names strimzi-cluster-operator and its content
• Edit it and change the following line:

rootLogger.level = ${env:STRIMZI_LOG_LEVEL:-INFO}

• to:

rootLogger.level = ${env:STRIMZI_LOG_LEVEL:-DEBUG}

• Open the operator log and wait for the log level to change:
  • kubectl logs deployment/strimzi-cluster-operator -f
  • Wait for the DEBUG messages to show up
  • Notice the pod did not need to restart

(If you installed the operator using OperatorHub, the config map and pod will be in another namespace (e.g. openshift-operators) and might have different name.)

Kafka brokers

• We can also dynamically change log levels for Kafka
  • Edit the Kafka resource
  • Set the log level for to

    logging:
      type: inline
      loggers:
        log4j.logger.org.apache.zookeeper: "DEBUG"

• On your own:
  • Try the same for The Entity Operators, Kafka Connect, HTTP Bridge or for Mirror Maker

Metrics

• On OpenShift, install the Prometheus operators from Operator Hub and deploy Grafana and Prometheus

  • kubectl apply -f metrics/prometheus-server.yaml
  • kubectl apply -f metrics/grafana-operator.yaml
  • kubectl apply -f metrics/grafana-server.yaml

• On Kubernetes, install the Grafana and Prometheus operators from YAMLs and deploy Grafana and Prometheus

  • kubectl apply -f metrics/prometheus-operator.yaml
  • kubectl apply -f metrics/prometheus-server.yaml
  • kubectl apply -f metrics/grafana-operator.yaml
  • kubectl apply -f metrics/grafana-server.yaml

• You can access the Prometheus and Grafana UIs using the OpenShift Routes or using port-forward

• Deploy the Kafka clients to generate some load

  • kubectl apply -f clients.yaml

Resource state metrics

• Exec into the Cluster Operator pod and run the following command
  • curl localhost:8080/metrics | grep strimzi_resource_state
  • Check the outcome showing the state of the custom resources: 1 => Ready, 0 => Not Ready

sh-4.2$ curl localhost:8080/metrics | grep strimzi_resource_state
# HELP strimzi_resource_state Current state of the resource: 1 ready, 0 fail
# TYPE strimzi_resource_state gauge
strimzi_resource_state{kind="Kafka",name="my-cluster",resource_namespace="myproject",} 1.0

• You can alternatively also check it in the Prometheus UI

Bridge metrics

• Deploy bridge with metrics enabled:
  • kubectl apply -f metrics-bridge.yaml
• Deploy the example HTTP clients
  • kubectl apply -f metrics-bridge-clients.yaml
• Open the Bridge dashboard in Grafana and check the metrics

Cruise Control metrics

• Open the Cruise Control dashboard in Grafana and check the metrics
• Scale the Kafka cluster to 5 replicas
• Trigger a rebalance
  • kubectl apply -f rebalance.yaml
• Wait until the rebalance proposal is ready
• Annotate it to execute the rebalance
  • kubectl annotate kafkarebalance my-rebalance strimzi.io/rebalance=approve
• Watch in the dashboard the progress

Scale sub-resource

• Scale the already deployed Kafka bridge to more replicas
  • kubectl scale kafkabridge my-bridge --replicas 3
  • Check how the number of replicas in the my-bridge resource changed to 3