我在 AWS EMR - 12 节点集群上运行 Spark/Scala 应用程序。我有多个转换发生，我写入 HDFS 并从 hdfs 回读以完成转换并最终写入 S3。
在这些转换之一中，我最近开始收到以下错误“
2018-08-10 20:05:31,106 [task-result-getter-2] WARN org.apache.spark.scheduler.TaskSetManager:66 - Lost task 44.0 in stage 30.0 (TID 4300, IP-address-here, executor 5): org.apache.hadoop.ipc.RemoteException(java.io.IOException): File /user/hadoop/working/xml/SD5256.20171030.5251246b-5475.xml.__temp could only be replicated to 0 nodes instead of minReplication (=1). There are 11 datanode(s) running and no node(s) are excluded in this operation.
at org.apache.hadoop.hdfs.server.blockmanagement.BlockManager.chooseTarget4NewBlock(BlockManager.java:1735)
at org.apache.hadoop.hdfs.server.namenode.FSDirWriteFileOp.chooseTargetForNewBlock(FSDirWriteFileOp.java:265)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getAdditionalBlock(FSNamesystem.java:2561)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.addBlock(NameNodeRpcServer.java:829)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.addBlock(ClientNamenodeProtocolServerSideTranslatorPB.java:510)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:447)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:989)
at org.apache.hadoop.ipc.Server$RpcCall.run(Server.java:847)
at org.apache.hadoop.ipc.Server$RpcCall.run(Server.java:790)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1836)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2486)
at org.apache.hadoop.ipc.Client.getRpcResponse(Client.java:1489)
at org.apache.hadoop.ipc.Client.call(Client.java:1435)
at org.apache.hadoop.ipc.Client.call(Client.java:1345)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:227)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:116)
at com.sun.proxy.$Proxy38.addBlock(Unknown Source)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.addBlock(ClientNamenodeProtocolTranslatorPB.java:444)
at sun.reflect.GeneratedMethodAccessor239.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:409)
at org.apache.hadoop.io.retry.RetryInvocationHandler$Call.invokeMethod(RetryInvocationHandler.java:163)
at org.apache.hadoop.io.retry.RetryInvocationHandler$Call.invoke(RetryInvocationHandler.java:155)
at org.apache.hadoop.io.retry.RetryInvocationHandler$Call.invokeOnce(RetryInvocationHandler.java:95)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:346)
at com.sun.proxy.$Proxy39.addBlock(Unknown Source)
at org.apache.hadoop.hdfs.DataStreamer.locateFollowingBlock(DataStreamer.java:1838)
at org.apache.hadoop.hdfs.DataStreamer.nextBlockOutputStream(DataStreamer.java:1638)
at org.apache.hadoop.hdfs.DataStreamer.run(DataStreamer.java:704)
根据一些文章和论坛成员的评论，我通过添加以下配置更新了 hdfs-site.xml：
<property>
<name>dfs.client.use.datanode.hostname</name>
<value>true</value>
</property>
<property>
<name>dfs.datanode.use.datanode.hostname</name>
<value>true</value>
</property>
有人可以帮我理解为什么我会收到这个错误吗？以及我需要在 hdfs-site.xml 中更新什么配置来解决这个问题。任何帮助表示赞赏。