Configuration & Environment Overrides

The cluster definition also supports overriding configuration properties and environment variables, either per role or per role group, where the more specific override (role group) has precedence over the less specific one (role).

Overriding certain properties which are set by the operator (such as the HTTP port) can interfere with the operator and can lead to problems.

Configuration Properties

For a role or role group, at the same level of config, you can specify: configOverrides for the runtime.properties. For example, if you want to set the druid.server.http.numThreads for the router to 100 adapt the routers section of the cluster resource like so:

routers:
  roleGroups:
    default:
      config: {}
      configOverrides:
        runtime.properties:
          druid.server.http.numThreads: "100"
      replicas: 1

Just as for the config, it is possible to specify this at role level as well:

routers:
  configOverrides:
    runtime.properties:
      druid.server.http.numThreads: "100"
  roleGroups:
    default:
      config: {}
      replicas: 1

All override property values must be strings.

For a full list of configuration options please refer to the Druid Configuration Reference.

Environment Variables

In a similar fashion, environment variables can be (over)written. For example per role group:

routers:
  roleGroups:
    default:
      config: {}
      envOverrides:
        MY_ENV_VAR: "MY_VALUE"
      replicas: 1

or per role:

routers:
  envOverrides:
    MY_ENV_VAR: "MY_VALUE"
  roleGroups:
    default:
      config: {}
      replicas: 1