记录一次 hadoop yarn resourceManager无故切换的故障

某日 收到告警 线上集群rm切换 观察resourcemanager 日志报错如下

 这行不明显 再看看其他日志报错

 在 app attempt_removed 时候发生了空指针错误

    break;
    case APP_ATTEMPT_REMOVED:
      if (!(event instanceof AppAttemptRemovedSchedulerEvent)) {
        throw new RuntimeException("Unexpected event type: " + event);
      }
      AppAttemptRemovedSchedulerEvent appAttemptRemovedEvent =
          (AppAttemptRemovedSchedulerEvent) event;
      removeApplicationAttempt(
          appAttemptRemovedEvent.getApplicationAttemptID(),
          appAttemptRemovedEvent.getFinalAttemptState(),
          appAttemptRemovedEvent.getKeepContainersAcrossAppAttempts());
      break;
    case CONTAINER_EXPIRED:

定位到代码问题在这里 新增标记内容

private void removeApplicationAttempt(
      ApplicationAttemptId applicationAttemptId,
      RMAppAttemptState rmAppAttemptFinalState, boolean keepContainers) {
    LOG.info("Application " + applicationAttemptId + " is done." +
        " finalState=" + rmAppAttemptFinalState);
    try {
      writeLock.lock();
      SchedulerApplication<FSAppAttempt> application =
        applications.get(applicationAttemptId.getApplicationId());
      FSAppAttempt attempt = getSchedulerApp(applicationAttemptId);

      if (attempt == null || application == null) {
        LOG.info("Unknown application " + applicationAttemptId + " has completed!");
        return;
      }
     //已经停止了就不用再次停止了 新增
      // Check if the attempt is already stopped and don't stop it twice.
      if (attempt.isStopped()) {
        LOG.info("Application " + applicationAttemptId + " has already been "
                + "stopped!");
        return;
      }

      // Release all the running containers
      for (RMContainer rmContainer : attempt.getLiveContainers()) {
        if (keepContainers
          && rmContainer.getState().equals(RMContainerState.RUNNING)) {
          // do not kill the running container in the case of work-preserving AM
          // restart.
          LOG.info("Skip killing " + rmContainer.getContainerId());
          continue;
        }
        super.completedContainer(rmContainer,
          SchedulerUtils.createAbnormalContainerStatus(
            rmContainer.getContainerId(),
            SchedulerUtils.COMPLETED_APPLICATION),
          RMContainerEventType.KILL);
      }

增加如下代码

 @Override
  public String moveApplication(ApplicationId appId,
      String queueName) throws YarnException {
    try {
      writeLock.lock();
      SchedulerApplication<FSAppAttempt> app = applications.get(appId);
      if (app == null) {
        throw new YarnException("App to be moved " + appId + " not found.");
      }
      FSAppAttempt attempt = (FSAppAttempt) app.getCurrentAppAttempt();
      // To serialize with FairScheduler#allocate, synchronize on app attempt
      try {
        attempt.getWriteLock().lock();
        FSLeafQueue oldQueue = (FSLeafQueue) app.getQueue();
        // Check if the attempt is already stopped: don't move stopped app
        // attempt. The attempt has already been removed from all queues.
        if (attempt.isStopped()) {
          LOG.info("Application " + appId + " is stopped and can't be moved!"throw new YarnException("Application " ++ " is stopped and can't be moved!");
        }
        String destQueueName = handleMoveToPlanQueue(queueName);
        FSLeafQueue targetQueue = queueMgr.getLeafQueue(destQueueName, false);
        if (targetQueue == null) {
          throw new YarnException("Target queue " + queueName
            + " not found or is not a leaf queue.");
        }
        if (targetQueue == oldQueue) {
          return oldQueue.getQueueName();
        }

private void executeMove(SchedulerApplication<FSAppAttempt> app,
      FSAppAttempt attempt, FSLeafQueue oldQueue, FSLeafQueue newQueue) {
    // Check current runs state. Do not remove the attempt from the queue until
    // after the check has been performed otherwise it could remove the app
    // from a queue without moving it to a new queue.
    boolean wasRunnable = oldQueue.isRunnableApp(attempt);
    // if app was not runnable before, it may be runnable now
    boolean nowRunnable = maxRunningEnforcer.canAppBeRunnable(newQueue,
        attempt.getUser());
    if (wasRunnable && !nowRunnable) {
      throw new IllegalStateException("Should have already verified that app "
          + attempt.getApplicationId() + " would be runnable in new queue");
    }

    // Now it is safe to remove from the queue.
    oldQueue.removeApp(attempt);

    if (wasRunnable) {
      maxRunningEnforcer.untrackRunnableApp(attempt);
    } else if (nowRunnable) {
      // App has changed from non-runnable to runnable
      maxRunningEnforcer.untrackNonRunnableApp(attempt);
    }
    
    attempt.move(newQueue); // This updates all the metrics
    app.setQueue(newQueue);
    newQueue.addApp(attempt, nowRunnable);
    
    if (nowRunnable) {
      maxRunningEnforcer.trackRunnableApp(attempt);
    }
    if (wasRunnable) {
      maxRunningEnforcer.updateRunnabilityOnAppRemoval(attempt, oldQueue);
    }
  }

问题解决 

参考 https://issues.apache.org/jira/secure/attachment/12841441/YARN-5136.2.patch