Chapter 55. CruiseControlSpec schema reference Used in: KafkaSpec Full list of CruiseControlSpec schema properties Configures a Cruise Control cluster. Configuration options relate to: Goals configuration Capacity limits for resource distribution goals 55.1. config Use the config properties to configure Cruise Control options as keys. The values can be one of the following JSON types: String Number Boolean Exceptions You can specify and configure the options listed in the Cruise Control documentation . However, Streams for Apache Kafka takes care of configuring and managing options related to the following, which cannot be changed: Security (encryption, authentication, and authorization) Connection to the Kafka cluster Client ID configuration ZooKeeper connectivity Web server configuration Self healing Properties with the following prefixes cannot be set: bootstrap.servers capacity.config.file client.id failed.brokers.zk.path kafka.broker.failure.detection.enable metric.reporter.sampler.bootstrap.servers network. request.reason.required security. self.healing. ssl. topic.config.provider.class two.step. webserver.accesslog. webserver.api.urlprefix webserver.http. webserver.session.path zookeeper. If the config property contains an option that cannot be changed, it is disregarded, and a warning message is logged to the Cluster Operator log file. All other supported options are forwarded to Cruise Control, including the following exceptions to the options configured by Streams for Apache Kafka: Any ssl configuration for supported TLS versions and cipher suites Configuration for webserver properties to enable Cross-Origin Resource Sharing (CORS) Example Cruise Control configuration apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka metadata: name: my-cluster spec: # ... cruiseControl: # ... config: # Note that `default.goals` (superset) must also include all `hard.goals` (subset) default.goals: > com.linkedin.kafka.cruisecontrol.analyzer.goals.RackAwareGoal, com.linkedin.kafka.cruisecontrol.analyzer.goals.ReplicaCapacityGoal hard.goals: > com.linkedin.kafka.cruisecontrol.analyzer.goals.RackAwareGoal cpu.balance.threshold: 1.1 metadata.max.age.ms: 300000 send.buffer.bytes: 131072 webserver.http.cors.enabled: true webserver.http.cors.origin: "*" webserver.http.cors.exposeheaders: "User-Task-ID,Content-Type" # ... 55.2. Cross-Origin Resource Sharing (CORS) Cross-Origin Resource Sharing (CORS) is a HTTP mechanism for controlling access to REST APIs. Restrictions can be on access methods or originating URLs of client applications. You can enable CORS with Cruise Control using the webserver.http.cors.enabled property in the config . When enabled, CORS permits read access to the Cruise Control REST API from applications that have different originating URLs than Streams for Apache Kafka. This allows applications from specified origins to use GET requests to fetch information about the Kafka cluster through the Cruise Control API. For example, applications can fetch information on the current cluster load or the most recent optimization proposal. POST requests are not permitted. Note For more information on using CORS with Cruise Control, see REST APIs in the Cruise Control Wiki . Enabling CORS for Cruise Control You enable and configure CORS in Kafka.spec.cruiseControl.config . apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka metadata: name: my-cluster spec: # ... cruiseControl: # ... config: webserver.http.cors.enabled: true 1 webserver.http.cors.origin: "*" 2 webserver.http.cors.exposeheaders: "User-Task-ID,Content-Type" 3 # ... 1 Enables CORS. 2 Specifies permitted origins for the Access-Control-Allow-Origin HTTP response header. You can use a wildcard or specify a single origin as a URL. If you use a wildcard, a response is returned following requests from any origin. 3 Exposes specified header names for the Access-Control-Expose-Headers HTTP response header. Applications in permitted origins can read responses with the specified headers. 55.3. Cruise Control REST API security The Cruise Control REST API is secured with HTTP Basic authentication and SSL to protect the cluster against potentially destructive Cruise Control operations, such as decommissioning Kafka brokers. We recommend that Cruise Control in Streams for Apache Kafka is only used with these settings enabled . However, it is possible to disable these settings by specifying the following Cruise Control configuration: To disable the built-in HTTP Basic authentication, set webserver.security.enable to false . To disable the built-in SSL, set webserver.ssl.enable to false . Cruise Control configuration to disable API authorization, authentication, and SSL apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka metadata: name: my-cluster spec: # ... cruiseControl: config: webserver.security.enable: false webserver.ssl.enable: false # ... 55.4. brokerCapacity Cruise Control uses capacity limits to determine if optimization goals for resource capacity limits are being broken. There are four goals of this type: DiskCapacityGoal - Disk utilization capacity CpuCapacityGoal - CPU utilization capacity NetworkInboundCapacityGoal - Network inbound utilization capacity NetworkOutboundCapacityGoal - Network outbound utilization capacity You specify capacity limits for Kafka broker resources in the brokerCapacity property in Kafka.spec.cruiseControl . They are enabled by default and you can change their default values. Capacity limits can be set for the following broker resources: cpu - CPU resource in millicores or CPU cores (Default: 1) inboundNetwork - Inbound network throughput in byte units per second (Default: 10000KiB/s) outboundNetwork - Outbound network throughput in byte units per second (Default: 10000KiB/s) For network throughput, use an integer value with standard OpenShift byte units (K, M, G) or their bibyte (power of two) equivalents (Ki, Mi, Gi) per second. Note Disk and CPU capacity limits are automatically generated by Streams for Apache Kafka, so you do not need to set them. In order to guarantee accurate rebalance proposals when using CPU goals, you can set CPU requests equal to CPU limits in Kafka.spec.kafka.resources . That way, all CPU resources are reserved upfront and are always available. This configuration allows Cruise Control to properly evaluate the CPU utilization when preparing the rebalance proposals based on CPU goals. In cases where you cannot set CPU requests equal to CPU limits in Kafka.spec.kafka.resources , you can set the CPU capacity manually for the same accuracy. Example Cruise Control brokerCapacity configuration using bibyte units apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka metadata: name: my-cluster spec: # ... cruiseControl: # ... brokerCapacity: cpu: "2" inboundNetwork: 10000KiB/s outboundNetwork: 10000KiB/s # ... 55.5. Capacity overrides Brokers might be running on nodes with heterogeneous network or CPU resources. If that's the case, specify overrides that set the network capacity and CPU limits for each broker. The overrides ensure an accurate rebalance between the brokers. Override capacity limits can be set for the following broker resources: cpu - CPU resource in millicores or CPU cores (Default: 1) inboundNetwork - Inbound network throughput in byte units per second (Default: 10000KiB/s) outboundNetwork - Outbound network throughput in byte units per second (Default: 10000KiB/s) An example of Cruise Control capacity overrides configuration using bibyte units apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka metadata: name: my-cluster spec: # ... cruiseControl: # ... brokerCapacity: cpu: "1" inboundNetwork: 10000KiB/s outboundNetwork: 10000KiB/s overrides: - brokers: [0] cpu: "2.755" inboundNetwork: 20000KiB/s outboundNetwork: 20000KiB/s - brokers: [1, 2] cpu: 3000m inboundNetwork: 30000KiB/s outboundNetwork: 30000KiB/s CPU capacity is determined using configuration values in the following order of precedence, with the highest priority first: Kafka.spec.cruiseControl.brokerCapacity.overrides.cpu that define custom CPU capacity limits for individual brokers Kafka.cruiseControl.brokerCapacity.cpu that defines custom CPU capacity limits for all brokers in the kafka cluster Kafka.spec.kafka.resources.requests.cpu that defines the CPU resources that are reserved for each broker in the Kafka cluster. Kafka.spec.kafka.resources.limits.cpu that defines the maximum CPU resources that can be consumed by each broker in the Kafka cluster. This order of precedence is the sequence in which different configuration values are considered when determining the actual capacity limit for a Kafka broker. For example, broker-specific overrides take precedence over capacity limits for all brokers. If none of the CPU capacity configurations are specified, the default CPU capacity for a Kafka broker is set to 1 CPU core. For more information, refer to the BrokerCapacity schema reference . 55.6. logging Cruise Control has its own configurable logger: rootLogger.level Cruise Control uses the Apache log4j2 logger implementation. Use the logging property to configure loggers and logger levels. You can set the log levels by specifying the logger and level directly (inline) or use a custom (external) ConfigMap. If a ConfigMap is used, you set logging.valueFrom.configMapKeyRef.name property to the name of the ConfigMap containing the external logging configuration. Inside the ConfigMap, the logging configuration is described using log4j.properties . Both logging.valueFrom.configMapKeyRef.name and logging.valueFrom.configMapKeyRef.key properties are mandatory. A ConfigMap using the exact logging configuration specified is created with the custom resource when the Cluster Operator is running, then recreated after each reconciliation. If you do not specify a custom ConfigMap, default logging settings are used. If a specific logger value is not set, upper-level logger settings are inherited for that logger. Here we see examples of inline and external logging. The inline logging specifies the root logger level. You can also set log levels for specific classes or loggers by adding them to the loggers property. Inline logging apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka # ... spec: cruiseControl: # ... logging: type: inline loggers: rootLogger.level: INFO logger.exec.name: com.linkedin.kafka.cruisecontrol.executor.Executor 1 logger.exec.level: TRACE 2 logger.go.name: com.linkedin.kafka.cruisecontrol.analyzer.GoalOptimizer 3 logger.go.level: DEBUG 4 # ... 1 Creates a logger for the Cruise Control Executor class. 2 Sets the logging level for the Executor class. 3 Creates a logger for the Cruise Control GoalOptimizer class. 4 Sets the logging level for the GoalOptimizer class. Note When investigating an issue with Cruise Control, it's usually sufficient to change the rootLogger to DEBUG to get more detailed logs. However, keep in mind that setting the log level to DEBUG may result in a large amount of log output and may have performance implications. External logging apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka # ... spec: cruiseControl: # ... logging: type: external valueFrom: configMapKeyRef: name: customConfigMap key: cruise-control-log4j.properties # ... Garbage collector (GC) Garbage collector logging can also be enabled (or disabled) using the jvmOptions property . 55.7. CruiseControlSpec schema properties Property Property type Description image string The container image used for Cruise Control pods. If no image name is explicitly specified, the image name corresponds to the name specified in the Cluster Operator configuration. If an image name is not defined in the Cluster Operator configuration, a default value is used. tlsSidecar TlsSidecar The tlsSidecar property has been deprecated. TLS sidecar configuration. resources ResourceRequirements CPU and memory resources to reserve for the Cruise Control container. livenessProbe Probe Pod liveness checking for the Cruise Control container. readinessProbe Probe Pod readiness checking for the Cruise Control container. jvmOptions JvmOptions JVM Options for the Cruise Control container. logging InlineLogging , ExternalLogging Logging configuration (Log4j 2) for Cruise Control. template CruiseControlTemplate Template to specify how Cruise Control resources, Deployments and Pods , are generated. brokerCapacity BrokerCapacity The Cruise Control brokerCapacity configuration. config map The Cruise Control configuration. For a full list of configuration options refer to https://github.com/linkedin/cruise-control/wiki/Configurations . Note that properties with the following prefixes cannot be set: bootstrap.servers, client.id, zookeeper., network., security., failed.brokers.zk.path,webserver.http., webserver.api.urlprefix, webserver.session.path, webserver.accesslog., two.step., request.reason.required,metric.reporter.sampler.bootstrap.servers, capacity.config.file, self.healing., ssl., kafka.broker.failure.detection.enable, topic.config.provider.class (with the exception of: ssl.cipher.suites, ssl.protocol, ssl.enabled.protocols, webserver.http.cors.enabled, webserver.http.cors.origin, webserver.http.cors.exposeheaders, webserver.security.enable, webserver.ssl.enable). metricsConfig JmxPrometheusExporterMetrics Metrics configuration.

Commands:
apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka metadata: name: my-cluster spec: # cruiseControl: # config: # Note that `default.goals` (superset) must also include all `hard.goals` (subset) default.goals: > com.linkedin.kafka.cruisecontrol.analyzer.goals.RackAwareGoal, com.linkedin.kafka.cruisecontrol.analyzer.goals.ReplicaCapacityGoal hard.goals: > com.linkedin.kafka.cruisecontrol.analyzer.goals.RackAwareGoal cpu.balance.threshold: 1.1 metadata.max.age.ms: 300000 send.buffer.bytes: 131072 webserver.http.cors.enabled: true webserver.http.cors.origin: "*" webserver.http.cors.exposeheaders: "User-Task-ID,Content-Type" #
apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka metadata: name: my-cluster spec: # cruiseControl: # config: webserver.http.cors.enabled: true 1 webserver.http.cors.origin: "*" 2 webserver.http.cors.exposeheaders: "User-Task-ID,Content-Type" 3 #
apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka metadata: name: my-cluster spec: # cruiseControl: config: webserver.security.enable: false webserver.ssl.enable: false
apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka metadata: name: my-cluster spec: # cruiseControl: # brokerCapacity: cpu: "2" inboundNetwork: 10000KiB/s outboundNetwork: 10000KiB/s #
apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka metadata: name: my-cluster spec: # cruiseControl: # brokerCapacity: cpu: "1" inboundNetwork: 10000KiB/s outboundNetwork: 10000KiB/s overrides: - brokers: [0] cpu: "2.755" inboundNetwork: 20000KiB/s outboundNetwork: 20000KiB/s - brokers: [1, 2] cpu: 3000m inboundNetwork: 30000KiB/s outboundNetwork: 30000KiB/s
apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka spec: cruiseControl: # logging: type: inline loggers: rootLogger.level: INFO logger.exec.name: com.linkedin.kafka.cruisecontrol.executor.Executor 1 logger.exec.level: TRACE 2 logger.go.name: com.linkedin.kafka.cruisecontrol.analyzer.GoalOptimizer 3 logger.go.level: DEBUG 4 #
apiVersion: kafka.strimzi.io/v1beta2 kind: Kafka spec: cruiseControl: # logging: type: external valueFrom: configMapKeyRef: name: customConfigMap key: cruise-control-log4j.properties #