void addDisableSecurityHookStage(Cluster cluster,
                                     String clusterHostInfoJson,
                                     String hostParamsJson,
                                     Map<String, String> commandParameters,
                                     RoleCommandOrder roleCommandOrder,
                                     RequestStageContainer requestStageContainer)
      throws AmbariException {
      Stage stage = createNewStage(requestStageContainer.getLastStageId(),
        cluster,
        requestStageContainer.getId(),
        "Disable security",
        StageUtils.getGson().toJson(commandParameters),
        hostParamsJson);
      addDisableSecurityCommandToAllServices(cluster, stage);
      RoleGraph roleGraph = roleGraphFactory.createNew(roleCommandOrder);
      roleGraph.build(stage);

      requestStageContainer.addStages(roleGraph.getStages());
    }
Send a custom command to the KERBEROS_CLIENT to check if there are missing keytabs on each hosts.
ambari-server/src/main/java/org/apache/ambari/server/controller/KerberosHelperImpl.java