JMX

If your Kafka brokers expose JMX metrics Kouncil can take advantage of that, displaying additional metrics. This is done using advanced config, where you can specify JMX parameters for each broker, like so:

kouncil:
  clusters:
    - name: transaction-cluster
      brokers:
        - host: 192.10.0.1
          port: 9092
          jmxPort: 5088
        - host: 192.10.0.2
          port: 9093
          jmxPort: 5089
        - host: 192.10.0.3
          port: 9094
          jmxPort: 5090

This example assumes that broker does not require any kind of authentication to access JMX metrics - you only need to specify JMX port. If that's not the case, and JMX authentication is turned on, you can also specify JMX user and password:

kouncil:
  clusters:
    - name: transaction-cluster
      brokers:
        - host: 192.10.0.1
          port: 9092
          jmxPort: 5088
          jmxUser: jmxAdmin
          jmxPassword: jmxPassword
        - host: 192.10.0.2
          port: 9093
          jmxPort: 5088
          jmxUser: jmxAdmin
          jmxPassword: jmxPassword
        - host: 192.10.0.3
          port: 9094
          jmxPort: 5088
          jmxUser: jmxAdmin
          jmxPassword: jmxPassword

It quickly becomes clear, that in many cases those properties (jmxPort, jmxUser, jmxPassword) will be identical for each of the brokers inside the cluster. For that reason, you can also specify them on a cluster level, and they will propagate to each broker:

kouncil:
  clusters:
    - name: transaction-cluster
      jmxPort: 5088
      jmxUser: jmxAdmin
      jmxPassword: jmxPassword
      brokers:
        - host: 192.10.0.1
          port: 9092    
        - host: 192.10.0.2
          port: 9093
        - host: 192.10.0.3
          port: 9094

All brokers inside transaction-cluster will share the same JMX configuration (jmxPort = 5088, jmxUser = jmxAdmin, jmxPassword = jmxPassword).

Propagation of JMX parameters works independently for each of those parameters. For example, each of the brokers may have the same JMX user and password, but different port:

kouncil:
  clusters:
    - name: transaction-cluster
      jmxUser: jmxAdmin
      jmxPassword: jmxPassword
      brokers:
        - host: 192.10.0.1
          port: 9092
          jmxPort: 5088
        - host: 192.10.0.2
          port: 9093
          jmxPort: 5089
        - host: 192.10.0.3
          port: 9094
          jmxPort: 5090

In the case of both simple and advanced configuration being present, the advanced configuration takes precedence.