// Module included in the following assemblies:
//
// assembly-evaluation.adoc

[id='proc-kafka-cluster-{context}']
= Creating a cluster

With Strimzi installed, you create a Kafka cluster, then a topic within the cluster.

When you create a cluster, the Cluster Operator you deployed when installing Strimzi watches for new Kafka resources.

.Prerequisites

* For the Kafka cluster, ensure a Cluster Operator is deployed.
* For the topic, you must have a running Kafka cluster.

.Procedure

. Log in to the Kubernetes cluster as a non-privileged user.

. Create a new `my-cluster` Kafka cluster with one ZooKeeper and one Kafka broker.
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* Use `persistent-claim` storage
* Expose the Kafka cluster outside of the Kubernetes cluster using an external listener configured to use a `nodeport`.
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--
[source,yaml,subs=attributes+]
----
cat << EOF | kubectl create -n my-kafka-project -f -
apiVersion: {KafkaApiVersion}
kind: Kafka
metadata:
  name: my-cluster
spec:
  kafka:
    replicas: 1
    listeners:
      - name: plain
        port: 9092
        type: internal
        tls: false
      - name: tls
        port: 9093
        type: internal
        tls: true
        authentication:
          type: tls
      - name: external
        port: 9094
        type: nodeport
        tls: false
    storage:
      type: jbod
      volumes:
      - id: 0
        type: persistent-claim
        size: 100Gi
        deleteClaim: false
    config:
      offsets.topic.replication.factor: 1
      transaction.state.log.replication.factor: 1
      transaction.state.log.min.isr: 1
  zookeeper:
    replicas: 1
    storage:
      type: persistent-claim
      size: 100Gi
      deleteClaim: false
  entityOperator:
    topicOperator: {}
    userOperator: {}
EOF
----
--

. Wait for the cluster to be deployed:
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[source,shell,subs="attributes+"]
----
kubectl wait kafka/my-cluster --for=condition=Ready --timeout=300s -n my-kafka-project
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. When your cluster is ready, create a topic to publish and subscribe from your external client.
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Create the following `my-topic` custom resource definition with 3 partitions and replication factor 1 in the `my-cluster` Kafka cluster:
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[source, yaml, subs=attributes+]
----
cat << EOF | kubectl create -n my-kafka-project -f -
apiVersion: {KafkaApiVersion}
kind: KafkaTopic
metadata:
  name: my-topic
  labels:
    strimzi.io/cluster: "my-cluster"
spec:
  partitions: 3
  replicas: 1
EOF
----
