private Map<String, Map<String, String>> config(String clusterName) throws AmbariException {
    return configHelper.getEffectiveConfigProperties(clusterName, null);
  }
I'm a special {@link MetricHostProvider} that can override default component host names.
ambari-server/src/main/java/org/apache/ambari/server/controller/internal/OverriddenMetricsHostProvider.java