private StageWrapper getRegenerateKeytabsWrapper(UpgradeContext ctx, ExecuteStage execution) {
    Task task = execution.task;
    HostsType hosts = HostsType.healthy(ctx.getCluster());

    return new StageWrapper(StageWrapper.Type.REGENERATE_KEYTABS, execution.title,
        new TaskWrapper(null, null, hosts.getHosts(), task));
  }
Return a {@link StageWrapper} for regeneration of keytabs.

@param ctx
         Upgrade Context
@param execution
         Execution Stage
@return a {@link StageWrapper} which will regenerate keytabs on all hosts.
ambari-server/src/main/java/org/apache/ambari/server/stack/upgrade/ClusterGrouping.java