@Override
  protected void startUp() throws Exception {
    Map<String, Cluster> clusterMap = m_clustersProvider.get().getClusters();
    for (Cluster cluster : clusterMap.values()) {
      for (AlertDefinitionEntity entity : m_dao.findBySourceType(cluster.getClusterId(), SourceType.SERVER)) {
        // don't schedule disabled alert definitions
        if (!entity.getEnabled()) {
          continue;
        }
        // schedule the Runnable for the definition
        scheduleRunnable(entity);
      }
    }
  }
{@inheritDoc}
<p/>
Loads all of the definitions with SERVER source type and schedules
the ones that are enabled.
ambari-server/src/main/java/org/apache/ambari/server/state/services/AmbariServerAlertService.java