java - 从 MySQL 数据库导入时无法复制到 Hadoop 中的 Datanode

Question

我正在尝试将数据从 mysql 表导入到 hdfs。我正在使用下面的 sqoop 导入命令

sqoop import --connect jdbc:mysql://localhost:3306/employee --username root --password *** --table Emp --m 1

我收到以下错误

16/05/07 20:01:18 ERROR tool.ImportTool: Encountered IOException running import job: java.io.FileNotFoundException: File does not exist: hdfs://localhost:54310/usr/lib/sqoop/lib/parquet-format-2.0.0.jar
at org.apache.hadoop.hdfs.DistributedFileSystem$18.doCall(DistributedFileSystem.java:1122)
at org.apache.hadoop.hdfs.DistributedFileSystem$18.doCall(DistributedFileSystem.java:1114)
at org.apache.hadoop.fs.FileSystemLinkResolver.resolve(FileSystemLinkResolver.java:81)
at org.apache.hadoop.hdfs.DistributedFileSystem.getFileStatus(DistributedFileSystem.java:1114)
at org.apache.hadoop.mapreduce.filecache.ClientDistributedCacheManager.getFileStatus(ClientDistributedCacheManager.java:288)
at org.apache.hadoop.mapreduce.filecache.ClientDistributedCacheManager.getFileStatus(ClientDistributedCacheManager.java:224)
at org.apache.hadoop.mapreduce.filecache.ClientDistributedCacheManager.determineTimestamps(ClientDistributedCacheManager.java:93)
at org.apache.hadoop.mapreduce.filecache.ClientDistributedCacheManager.determineTimestampsAndCacheVisibilities(ClientDistributedCacheManager.java:57)
at org.apache.hadoop.mapreduce.JobSubmitter.copyAndConfigureFiles(JobSubmitter.java:269)
at org.apache.hadoop.mapreduce.JobSubmitter.copyAndConfigureFiles(JobSubmitter.java:390)
at org.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:483)
at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1296)
at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1293)
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.mapreduce.Job.submit(Job.java:1293)
at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:1314)
at org.apache.sqoop.mapreduce.ImportJobBase.doSubmitJob(ImportJobBase.java:196)
at org.apache.sqoop.mapreduce.ImportJobBase.runJob(ImportJobBase.java:169)
at org.apache.sqoop.mapreduce.ImportJobBase.runImport(ImportJobBase.java:266)
at org.apache.sqoop.manager.SqlManager.importTable(SqlManager.java:673)
at org.apache.sqoop.manager.MySQLManager.importTable(MySQLManager.java:118)
at org.apache.sqoop.tool.ImportTool.importTable(ImportTool.java:497)
at org.apache.sqoop.tool.ImportTool.run(ImportTool.java:605)
at org.apache.sqoop.Sqoop.run(Sqoop.java:143)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:179)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:218)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:227)
at org.apache.sqoop.Sqoop.main(Sqoop.java:236)

我在 usr/lib/sqoop 文件夹中有 parquet-format-2.0.0.jar，但即使这样它也显示错误。

我尝试将所有 sqoop lib 导入到 hdfs，但随后我可以这样做，它会抛出以下错误

16/05/07 18:40:11 WARN hdfs.DFSClient: DataStreamer Exception org.apache.hadoop.ipc.RemoteException(java.io.IOException): File /usr/lib/sqoop/lib/xz-1.0.jar.COPYING could only be replicated to 0 nodes instead of minReplication (=1). There are 0 datanode(s) running and no 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:3200) 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

现在能做什么？我无法将 jar 文件复制到 HDFS，也无法将数据从 MySQL 导入到 HDFS。

我尝试过这个解决方案 sqoop import eror - File does not exist:

但无法从第二步继续。我还清除了缓存并重新启动了 Hadoop 文件系统。

谢谢

Answer 1

对于datanode复制错误，可能有以下原因:

Datanodes doesn’t have enough disk space to store the blocks

Namenode can not reach Datanode(s) or Datanode(s) could be down/unavailable

确保Namenode和Datanode之间的连接以及Datanode有足够的空间来存储新 block 。

如果有足够的磁盘空间，您需要重新格式化您的nameNode。