Configuration #

Specifying Operator Configuration #

The operator allows users to specify default configuration that will be shared by the Flink operator itself and the Flink deployments.

These configuration files are mounted externally via ConfigMaps. The Configuration files with default values are shipped in the Helm chart. It is recommended to review and adjust them if needed in the values.yaml file before deploying the Operator in production environments.

To append to the default configuration, simply define the flink-conf.yaml key in the defaultConfiguration section of the Helm values.yaml file:

defaultConfiguration:
  create: true
  # Set append to false to replace configuration files
  append: true
  flink-conf.yaml: |+
    # Flink Config Overrides
    kubernetes.operator.metrics.reporter.slf4j.factory.class: org.apache.flink.metrics.slf4j.Slf4jReporterFactory
    kubernetes.operator.metrics.reporter.slf4j.interval: 5 MINUTE

    kubernetes.operator.reconcile.interval: 15 s
    kubernetes.operator.observer.progress-check.interval: 5 s

To learn more about metrics and logging configuration please refer to the dedicated docs page.

Dynamic Operator Configuration #

The Kubernetes operator supports dynamic config changes through the operator ConfigMaps. Dynamic operator configuration is enabled by default, and can be disabled by setting kubernetes.operator.dynamic.config.enabled to false. Time interval for checking dynamic config changes is specified by kubernetes.operator.dynamic.config.check.interval of which default value is 5 minutes.

Verify whether dynamic operator configuration updates is enabled via the deploy/flink-kubernetes-operator log has:

2022-05-28 13:08:29,222 o.a.f.k.o.c.FlinkConfigManager [INFO ] Enabled dynamic config updates, checking config changes every PT5M

To change config values dynamically the ConfigMap can be directly edited via kubectl patch or kubectl edit command. For example to change the reschedule interval you can override kubernetes.operator.reconcile.interval.

Verify whether the config value of kubernetes.operator.reconcile.interval is updated to 30 seconds via the deploy/flink-kubernetes-operator log has:

2022-05-28 13:08:30,115 o.a.f.k.o.c.FlinkConfigManager [INFO ] Updating default configuration to {kubernetes.operator.reconcile.interval=PT30S}

Operator Configuration Reference #

System Configuration #

General operator system configuration. Cannot be overridden on a per-resource basis.

Resource/User Configuration #

These options can be configured on both an operator and a per-resource level. When set under spec.flinkConfiguration for the Flink resources it will override the default value provided in the operator default configuration (flink-conf.yaml).

System Metrics Configuration #

Operator system metrics configuration. Cannot be overridden on a per-resource basis.

Advanced System Configuration #

Advanced operator system configuration. Cannot be overridden on a per-resource basis.