无法将保存点从1.2.1还原为1.4

Question

我们已经用1.4版本部署了一个新的Flink实例。在尝试从旧的1.2.1部署恢复保存点时，尝试还原的所有作业都会出现相同的错误：

org.apache.flink.runtime.execution.SuppressRestartsException: Unrecoverable failure. This suppresses job restarts. Please check the stack trace for the root cause.
    at org.apache.flink.runtime.jobmanager.JobManager$$anonfun$org$apache$flink$runtime$jobmanager$JobManager$$submitJob$1.apply$mcV$sp(JobManager.scala:1360)
    at org.apache.flink.runtime.jobmanager.JobManager$$anonfun$org$apache$flink$runtime$jobmanager$JobManager$$submitJob$1.apply(JobManager.scala:1336)
    at org.apache.flink.runtime.jobmanager.JobManager$$anonfun$org$apache$flink$runtime$jobmanager$JobManager$$submitJob$1.apply(JobManager.scala:1336)
    at scala.concurrent.impl.Future$PromiseCompletingRunnable.liftedTree1$1(Future.scala:24)
    at scala.concurrent.impl.Future$PromiseCompletingRunnable.run(Future.scala:24)
    at akka.dispatch.TaskInvocation.run(AbstractDispatcher.scala:39)
    at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:415)
    at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
    at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
    at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
    at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
Caused by: java.lang.IllegalStateException: Legacy state (from Flink <= 1.1, created through the 'Checkpointed' interface) is no longer supported starting from Flink 1.4. Please rewrite your job to use 'CheckpointedFunction' instead!
    at org.apache.flink.util.Preconditions.checkState(Preconditions.java:195)
    at org.apache.flink.runtime.checkpoint.savepoint.SavepointV1Serializer.deserializeSubtaskState(SavepointV1Serializer.java:171)
    at org.apache.flink.runtime.checkpoint.savepoint.SavepointV1Serializer.deserialize(SavepointV1Serializer.java:96)
    at org.apache.flink.runtime.checkpoint.savepoint.SavepointV1Serializer.deserialize(SavepointV1Serializer.java:54)
    at org.apache.flink.runtime.checkpoint.savepoint.SavepointStore.loadSavepointWithHandle(SavepointStore.java:278)
    at org.apache.flink.runtime.checkpoint.savepoint.SavepointLoader.loadAndValidateSavepoint(SavepointLoader.java:70)
    at org.apache.flink.runtime.checkpoint.CheckpointCoordinator.restoreSavepoint(CheckpointCoordinator.java:1141)
    at org.apache.flink.runtime.jobmanager.JobManager$$anonfun$org$apache$flink$runtime$jobmanager$JobManager$$submitJob$1.apply$mcV$sp(JobManager.scala:1350)
    ... 10 more

错误信息：

遗产状态(来自Flink <= 1.1，通过“校验”接口创建)不再支持从Flink 1.4开始。请重写你的工作，用“CheckpointedFunction”代替！

但是，似乎是错误的，因为我们的另一个部署正在运行1.2.1。

文档页仍未更新为1.4：https://ci.apache.org/projects/flink/flink-docs-release-1.4/ops/upgrading.html，但在过去，并行性似乎一直是一个问题。我试过使用与保存点( savepoint )即将到来的工作相同的工作，并且仍然使用相同的问题。

有什么可以导致这件事的提示吗?如何解决呢？

谢谢!

Answer 1

所以，终于解决了这个问题。

我们开始在Flink 1.1中运行任务，然后将任务的保存点迁移到1.2.1。

看起来Flink 1.2.1并没有对保存点进行任何升级，所以它们仍然有旧的格式，Flink 1.4不支持这种格式。

解决方案是在Flink 1.3中运行我们的任务+保存点，并在那里创建一个新的保存点，它将以新的格式保存。此版本最终与Flink 1.4兼容:)

Answer 2

使用1.4.0版本，Flink不再支持从Checkpointed接口获取的状态恢复。要进行有状态升级，必须执行以下操作：

1. 在Flink 1.2.1上使用作业的保存点
2. 在所有有状态函数中将Checkpointed替换为CheckpointedFunction
3. 实现CheckpointedRestoring接口以从Checkpointed保存点恢复
4. 在Flink 1.2.1上执行修改后的作业，并接受第二个保存点
5. 从所有有状态函数中删除CheckpointedRestoring接口
6. 使用Flink 1.4.0上的第二个保存点运行修改过的作业

在迁移你的工作时，让我知道是否还有其他问题。