异常信息
代码语言：javascript复制java.net.ConnectException: Call From node4/192.168.179.143 to node4:8032 failed on connection exception: java.net.ConnectException: Connection refused; For more details see: http://wiki.apache.org/hadoop/ConnectionRefused
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:408)
at org.apache.hadoop.net.NetUtils.wrapWithMessage(NetUtils.java:791)
at org.apache.hadoop.net.NetUtils.wrapException(NetUtils.java:731)
at org.apache.hadoop.ipc.Client.call(Client.java:1474)
at org.apache.hadoop.ipc.Client.call(Client.java:1401)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:232)
at com.sun.proxy.$Proxy12.getNewApplication(Unknown Source)
at org.apache.hadoop.yarn.api.impl.pb.client.ApplicationClientProtocolPBClientImpl.getNewApplication(ApplicationClientProtocolPBClientImpl.java:217)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
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.$Proxy13.getNewApplication(Unknown Source)
at org.apache.hadoop.yarn.client.api.impl.YarnClientImpl.getNewApplication(YarnClientImpl.java:206)
at org.apache.hadoop.yarn.client.api.impl.YarnClientImpl.createApplication(YarnClientImpl.java:214)
at org.apache.hadoop.mapred.ResourceMgrDelegate.getNewJobID(ResourceMgrDelegate.java:187)
at org.apache.hadoop.mapred.YARNRunner.getNewJobID(YARNRunner.java:231)
at org.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:154)
at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1297)
at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1294)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1692)
at org.apache.hadoop.mapreduce.Job.submit(Job.java:1294)
at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:1315)
at org.apache.sqoop.mapreduce.ImportJobBase.doSubmitJob(ImportJobBase.java:200)
at org.apache.sqoop.mapreduce.ImportJobBase.runJob(ImportJobBase.java:173)
at org.apache.sqoop.mapreduce.ImportJobBase.runImport(ImportJobBase.java:270)
at org.apache.sqoop.manager.SqlManager.importTable(SqlManager.java:692)
at org.apache.sqoop.manager.MySQLManager.importTable(MySQLManager.java:127)
at org.apache.sqoop.tool.ImportTool.importTable(ImportTool.java:520)
at org.apache.sqoop.tool.ImportTool.run(ImportTool.java:628)
at org.apache.sqoop.Sqoop.run(Sqoop.java:147)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:183)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:234)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:243)
at org.apache.sqoop.Sqoop.main(Sqoop.java:252)
Caused by: java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:712)
at org.apache.hadoop.net.SocketIOWithTimeout.connect(SocketIOWithTimeout.java:206)
at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:530)
at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:494)
at org.apache.hadoop.ipc.Client$Connection.setupConnection(Client.java:609)
at org.apache.hadoop.ipc.Client$Connection.setupIOstreams(Client.java:707)
at org.apache.hadoop.ipc.Client$Connection.access$2800(Client.java:370)
at org.apache.hadoop.ipc.Client.getConnection(Client.java:1523)
at org.apache.hadoop.ipc.Client.call(Client.java:1440)
... 36 more错误定位
Connection refused我们不只到原因,可以向上追溯产生异常第一行
java.net.ConnectException: Call From node4/192.168.179.143 to node4:8032 failed on connection exception: java.net.ConnectException: Connection refused; For more details see: http://wiki.apache.org/hadoop/ConnectionRefused
异常解决
可以看到是连接8032的端口失败 ,我们可以查看8032是哪一个端口Hadoop默认端口 通过查看可以看出是我们ResourceManger的端口.jps命令查看RM是否启动,结果发现没有启动!!!
在node4启动RM,再次运行导入命令,问题得解
代码语言：javascript复制yarn-daemon.sh start resourcemanager总结
mr程序一直处于阻塞状态需要查看nodemanager, resourcemanager是否启动成功 #启动NM start-yarn.sh #勿忘记启动resourcemanager(8032 端口) yarn-daemon.sh start resourcemanager
