@Override
  public void deleteConfigGroup(Long id) throws AmbariException {
    ConfigGroup configGroup = clusterConfigGroups.get(id);
    if (configGroup == null) {
      throw new ConfigGroupNotFoundException(getClusterName(), id.toString());
    }

    LOG.debug("Deleting Config group, clusterName = {}, groupName = {}, groupId = {}, tag = {}",
      getClusterName(), configGroup.getName(), configGroup.getId(), configGroup.getTag());

    configGroup.delete();
    clusterConfigGroups.remove(id);

    configHelper.updateAgentConfigs(Collections.singleton(configGroup.getClusterName()));
  }
Make sure we load all the service host components.
We need this for live status checks.
ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClusterImpl.java