[Bug]: Zookeeper Validation Error on Kafka Cluster Update with KRaft Enabled

[yanmxa]

Description

When attempting to update the Kafka cluster, the following error occurs:

Kafka.kafka.strimzi.io "kafka" is invalid: [spec.zookeeper.replicas: Required value, spec.zookeeper.storage: Required value]

Configuration Details

The Kafka resource configuration is as follows:

apiVersion: kafka.strimzi.io/v1beta2
kind: Kafka
metadata:
  annotations:
    strimzi.io/kraft: enabled
    strimzi.io/node-pools: enabled
  creationTimestamp: "2024-11-14T04:16:15Z"
  generation: 2
  labels:
    global-hub.open-cluster-management.io/managed-by: global-hub-operator
  name: kafka
  namespace: multicluster-global-hub
  ownerReferences:
  - apiVersion: operator.open-cluster-management.io/v1alpha4
    blockOwnerDeletion: true
    controller: true
    kind: MulticlusterGlobalHub
    name: multiclusterglobalhub
    uid: 8aeaf2d3-07c4-4923-8284-f9f704dc7d84
  resourceVersion: "47817"
  uid: e692a4a6-86e7-4f2f-afe9-0bdbe0649823
spec:
  entityOperator:
    topicOperator: {}
    userOperator: {}
  kafka:
    authorization:
      type: simple
    config:
      default.replication.factor: 1
      min.insync.replicas: 1
      offsets.topic.replication.factor: 1
      transaction.state.log.min.isr: 1
      transaction.state.log.replication.factor: 1
    listeners:
    - name: plain
      port: 9092
      tls: false
      type: internal
    - authentication:
        type: tls
      configuration:
        bootstrap:
          nodePort: 30095
        brokers:
        - advertisedHost: 172.18.0.2
          broker: 0
      name: external
      port: 9095
      tls: true
      type: nodeport
    replicas: 1
    storage:
      type: ephemeral
    version: 3.7.0

Problem

Although the KRaft mode is enabled in the configuration, the system raises an error related to missing Zookeeper settings (spec.zookeeper.replicas and spec.zookeeper.storage), which should not be required in KRaft mode.

Request

Please investigate why Zookeeper configuration is still required when KRaft mode is enabled, or advise on any additional configuration needed to suppress these requirements in KRaft mode.

Steps to reproduce

No response

Expected behavior

With strimzi.io/kraft: enabled annotation, Zookeeper configuration should not be mandatory, as KRaft mode removes the need for Zookeeper.

Strimzi version

0.41.0

Kubernetes version

KinD cluster kubernetes version: v1.23.0

Installation method

No response

Infrastructure

No response

Configuration files and logs

No response

Additional context

No response

[katheris]

Hi @yanmxa, your Kafka CR doesn't look quite right. For example you have replicas and storage included, when those should be in your KafkaNodePool CR(s). What steps did you take before getting the error? Are you updating an existing Kafka cluster?

Here's an example of a valid KRaft cluster: https://github.com/strimzi/strimzi-kafka-operator/blob/main/examples/kafka/kraft/kafka-single-node.yaml

[scholzj]

It is not really clear where you get the error. If you get it when trying to create/update the resource in Kubernetes, it sounds like you did not update the CRDs.

[yanmxa]

When I attempt to update the PR, I encounter the above error.

Thanks @katheris and @scholzj!

1. I tried updating the existing Kafka CR without the replicas and storage fields even though I have configured them in the KafkaNodePool CR, but I received a validation error:

   Kafka.kafka.strimzi.io "kafka" is invalid: [spec.kafka.replicas: Required value, spec.kafka.storage: Required value]
   

   So I add the replicas and storage in the above CR.

2. It might be due to the lower CRD version. The CSV I’m currently using is strimzi-cluster-operator.v0.41.0. Let me try a higher version. :)

[scholzj]

As I said, if you get the error from kubectl, it is about the CRDs.

[yanmxa]

👍 @scholzj Got it! I tried it with Strimzi CSV 0.42.0, and the error is gone!