问题
I have HDP 2.2 running on CentOS within OracleVM on my local machine (Windows 7) in Pseudo Distro mode. Wanted to test it for remote submission and hence created a WordCount example in Eclipse running outside OVM and submitted as follows (example I chose is from somewhere else on the net itself)
Path inputPath = new Path("/hdfsinput");
Path outputDir = new Path("/hdfsoutput");
// Create configuration
Configuration conf = new Configuration(true);
// create inputPath on HDFS if needed
FileSystem hdfs = FileSystem.get(conf);
if (!hdfs.exists(inputPath))
hdfs.mkdirs(inputPath);
// Create job
Job job = new Job(conf, "WordCount");
job.setJarByClass(WordCountMapper.class);
// Setup MapReduce
job.setMapperClass(WordCountMapper.class);
job.setReducerClass(WordCountReducer.class);
job.setNumReduceTasks(1);
// Specify key / value
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(IntWritable.class);
// Input
FileInputFormat.addInputPath(job, inputPath);
job.setInputFormatClass(TextInputFormat.class);
// Output
FileOutputFormat.setOutputPath(job, outputDir);
job.setOutputFormatClass(TextOutputFormat.class);
// Delete output if exists
if (hdfs.exists(outputDir))
hdfs.delete(outputDir, true);
hdfs.close();
// Execute job
int code = job.waitForCompletion(true) ? 0 : 1;
System.out.println("output code => "+code);
System.exit(code);
Got following exception returned within Eclipse (as well as Namenode logs (sandbox.hortonworks.com:50070/logs/hadoop-hdfs-namenode-sandbox.hortonworks.com.log))
Namenode log:
2015-12-07 16:21:14,631 INFO blockmanagement.BlockManager BlockManager.java:setReplication(2710)) - Increasing replication from 1 to 10 for /user/root/.staging/job_1449505005810_0001/job.split
2015-12-07 16:21:14,690 INFO hdfs.StateChange FSNamesystem.java:saveAllocatedBlock(3663)) - BLOCK* allocateBlock: /user/root/.staging/job_1449505005810_0001/job.split. BP-1487918654-10.0.2.15-1418756667447 blk_1073742153_1339{blockUCState=UNDER_CONSTRUCTION, primaryNodeIndex=-1, replicas=[ReplicaUnderConstruction[[DISK]DS-b183a7df-9498-4b2c-87f5-4bfb2cf40ca3:NORMAL:10.0.2.15:50010|RBW]]}
2015-12-07 16:21:35,768 WARN blockmanagement.BlockPlacementPolicy (BlockPlacementPolicyDefault.java:chooseTarget(383)) - Failed to place enough replicas, still in need of 1 to reach 1 (unavailableStorages=[], storagePolicy=BlockStoragePolicy{HOT:7, storageTypes=[DISK], creationFallbacks=[], replicationFallbacks=[ARCHIVE]}, newBlock=true) For more information, please enable DEBUG log level on org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicy
2015-12-07 16:21:35,769 WARN blockmanagement.BlockPlacementPolicy (BlockPlacementPolicyDefault.java:chooseTarget(383)) - Failed to place enough replicas, still in need of 1 to reach 1 (unavailableStorages=[], storagePolicy=BlockStoragePolicy{HOT:7, storageTypes=[DISK], creationFallbacks=[], replicationFallbacks=[ARCHIVE]}, newBlock=true) For more information, please enable DEBUG log level on org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicy
2015-12-07 16:21:35,770 WARN protocol.BlockStoragePolicy (BlockStoragePolicy.java:chooseStorageTypes(160)) - Failed to place enough replicas: expected size is 1 but only 0 storage types can be selected (replication=1, selected=[], unavailable=[DISK], removed=[DISK], policy=BlockStoragePolicy{HOT:7, storageTypes=[DISK], creationFallbacks=[], replicationFallbacks=[ARCHIVE]})
2015-12-07 16:21:35,770 WARN blockmanagement.BlockPlacementPolicy (BlockPlacementPolicyDefault.java:chooseTarget(383)) - Failed to place enough replicas, still in need of 1 to reach 1 (unavailableStorages=[DISK], storagePolicy=BlockStoragePolicy{HOT:7, storageTypes=[DISK], creationFallbacks=[], replicationFallbacks=[ARCHIVE]}, newBlock=true) All required storage types are unavailable: unavailableStorages=[DISK], storagePolicy=BlockStoragePolicy{HOT:7, storageTypes=[DISK], creationFallbacks=[], replicationFallbacks=[ARCHIVE]}
2015-12-07 16:21:35,771 INFO ipc.Server (Server.java:run(2060)) - IPC Server handler 91 on 8020, call org.apache.hadoop.hdfs.protocol.ClientProtocol.addBlock from 10.0.2.2:54842 Call#25 Retry#0
java.io.IOException: File /user/root/.staging/job_1449505005810_0001/job.split could only be replicated to 0 nodes instead of minReplication (=1). There are 1 datanode(s) running and 1 node(s) are excluded in this operation.
at org.apache.hadoop.hdfs.server.blockmanagement.BlockManager.chooseTarget4NewBlock(BlockManager.java:1549)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getAdditionalBlock(FSNamesystem.java:3203)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.addBlock(NameNodeRpcServer.java:641)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.addBlock(ClientNamenodeProtocolServerSideTranslatorPB.java:482)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:619)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:962)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2039)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2035)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1628)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2033)
Eclipse Console....
org.apache.hadoop.ipc.RemoteException(java.io.IOException): File /user/root/.staging/job_1449505005810_0002/job.split could only be replicated to 0 nodes instead of minReplication (=1). There are 1 datanode(s) running and 1 node(s) are excluded in this operation.
at org.apache.hadoop.hdfs.server.blockmanagement.BlockManager.chooseTarget4NewBlock(BlockManager.java:1549)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getAdditionalBlock(FSNamesystem.java:3203)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.addBlock(NameNodeRpcServer.java:641)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.addBlock(ClientNamenodeProtocolServerSideTranslatorPB.java:482)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:619)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:962)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2039)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2035)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1628)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2033)
at org.apache.hadoop.ipc.Client.call(Client.java:1468)
at org.apache.hadoop.ipc.Client.call(Client.java:1399)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:232)
at com.sun.proxy.$Proxy14.addBlock(Unknown Source)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.addBlock(ClientNamenodeProtocolTranslatorPB.java:399)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:187)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:102)
at com.sun.proxy.$Proxy15.addBlock(Unknown Source)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.locateFollowingBlock(DFSOutputStream.java:1532)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.nextBlockOutputStream(DFSOutputStream.java:1349)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.run(DFSOutputStream.java:588)
Notice "WARN" statements in Namenode log. Based on those I enabled DEBUG mode on "org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicy" and rerun the Job to additionally get following exception in the namenode log before the original exception.
Namenode log (upon job resubmission):
2015-12-07 16:22:17,137 INFO blockmanagement.BlockManager (BlockManager.java:setReplication(2710)) - Increasing replication from 1 to 10 for /user/root/.staging/job_1449505005810_0002/job.split
2015-12-07 16:22:17,175 INFO hdfs.StateChange (FSNamesystem.java:saveAllocatedBlock(3663)) - BLOCK* allocateBlock: /user/root/.staging/job_1449505005810_0002/job.split. BP-1487918654-10.0.2.15-1418756667447 blk_1073742154_1340{blockUCState=UNDER_CONSTRUCTION, primaryNodeIndex=-1, replicas=[ReplicaUnderConstruction[[DISK]DS-b183a7df-9498-4b2c-87f5-4bfb2cf40ca3:NORMAL:10.0.2.15:50010|RBW]]}
2015-12-07 16:22:38,254 DEBUG blockmanagement.BlockPlacementPolicy (BlockPlacementPolicyDefault.java:chooseLocalRack(530)) - Failed to choose from local rack (location = /default-rack); the second replica is not found, retry choosing ramdomly
org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicy$NotEnoughReplicasException:
at org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseRandom(BlockPlacementPolicyDefault.java:691)
at org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseRandom(BlockPlacementPolicyDefault.java:606)
at org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseLocalRack(BlockPlacementPolicyDefault.java:512)
at org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseLocalStorage(BlockPlacementPolicyDefault.java:472)
at org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseTarget(BlockPlacementPolicyDefault.java:339)
at org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseTarget(BlockPlacementPolicyDefault.java:214)
at org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseTarget(BlockPlacementPolicyDefault.java:111)
at org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault.chooseTarget(BlockPlacementPolicyDefault.java:126)
at org.apache.hadoop.hdfs.server.blockmanagement.BlockManager.chooseTarget4NewBlock(BlockManager.java:1545)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getAdditionalBlock(FSNamesystem.java:3203)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.addBlock(NameNodeRpcServer.java:641)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.addBlock(ClientNamenodeProtocolServerSideTranslatorPB.java:482)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:619)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:962)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2039)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2035)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1628)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2033)
I have tried all Stack Overflow solutions for resolving exception "could only be replicated to 0 nodes instead of minReplication (=1). There are 1 datanode(s) running and 1 node(s) are excluded in this operation" but could not resolve it.
Tried formatting namenode
Tried to place all centOS configuration files in "/usr/hdp/2.2.0.0-2041/hadoop/conf" in windows local folder and included it in Eclipse classpath
Tried opening all ports to make it accessible from Eclipse (including 50010).
- Tried placing slaves and master files in /etc/hadoop
- And many others...
Upon examining code from BlockPlacementPolicyDefault (http://grepcode.com/file/repo1.maven.org/maven2/org.apache.hadoop/hadoop-hdfs/2.6.0/org/apache/hadoop/hdfs/server/blockmanagement/BlockPlacementPolicyDefault.java), I feel the error is due to faulty logic at 715 which always returns a 0 because the localnode is already added to excludednode Set.
703 int addIfIsGoodTarget(DatanodeStorageInfo storage,
704 Set<Node> excludedNodes,
705 long blockSize,
706 int maxNodesPerRack,
707 boolean considerLoad,
708 List<DatanodeStorageInfo> results,
709 boolean avoidStaleNodes,
710 StorageType storageType) {
711 if (isGoodTarget(storage, blockSize, maxNodesPerRack, considerLoad,
712 results, avoidStaleNodes, storageType)) {
713 results.add(storage);
714 // add node and related nodes to excludedNode
715 return addToExcludedNodes(storage.getDatanodeDescriptor(), excludedNodes);
716 } else {
717 return -1;
718 }
719 }
and thus the following lines will always be executed to throw exception (one needs to see entire code link above to make sense).
681 if (numOfReplicas>0) {
682 String detail = enableDebugLogging;
683 if (LOG.isDebugEnabled()) {
684 if (badTarget && builder != null) {
685 detail = builder.toString();
686 builder.setLength(0);
687 } else {
688 detail = "";
689 }
690 }
691 throw new NotEnoughReplicasException(detail);
692 }
But, may be I am just thinking too much and it is really a configuration issue with the parameters passed to following method (some of these parameters must be coming from HDFS configuration files)
652 final int newExcludedNodes = addIfIsGoodTarget(storages[i],
653 excludedNodes, blocksize, maxNodesPerRack, considerLoad, results,
654 avoidStaleNodes, type);
来源：https://stackoverflow.com/questions/34140531/hdp-2-2linux-centosoraclevm-hortonworks-fails-on-remote-submission-from-ecli