Question

从错误消息可以看出，保存与文件相关的特定块的副本存在问题。原因可能是，访问数据节点以保存特定块（块的副本）时出现问题。请参阅下面的完整日志：

我找到了另一个用户＆＃34; huasanyelao＆＃34; - https://stackoverflow.com/users/987275/huasanyelao也有类似的异常/问题，但用例不同。

现在，我们如何解决这些问题？我知道在所有情况下都没有固定的解决方案。
1.修复此类错误需要采取的直接步骤是什么？
2.如果有工作，我当时没有监控日志。我需要采取哪些方法来解决这些问题。

P.S：除了修复网络或访问问题外，我还应该遵循哪些其他方法。

错误日志：

*15/04/10 11:21:13 INFO impl.TimelineClientImpl: Timeline service address: http://your-name-node/ws/v1/timeline/
15/04/10 11:21:14 INFO client.RMProxy: Connecting to ResourceManager at your-name-node/xxx.xx.xxx.xx:0000
15/04/10 11:21:34 WARN hdfs.DFSClient: DataStreamer Exception
java.nio.channels.UnresolvedAddressException
        at sun.nio.ch.Net.checkAddress(Net.java:29)
        at sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:512)
        at org.apache.hadoop.net.SocketIOWithTimeout.connect(SocketIOWithTimeout.java:192)
        at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:529)
        at org.apache.hadoop.hdfs.DFSOutputStream.createSocketForPipeline(DFSOutputStream.java:1516)
        at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.createBlockOutputStream(DFSOutputStream.java:1318)
        at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.nextBlockOutputStream(DFSOutputStream.java:1272)
        at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.run(DFSOutputStream.java:525)
15/04/10 11:21:40 INFO hdfs.DFSClient: Could not complete /user/xxxxx/.staging/job_11111111111_1212/job.jar retrying...
15/04/10 11:21:46 INFO hdfs.DFSClient: Could not complete /user/xxxxx/.staging/job_11111111111_1212/job.jar retrying...
15/04/10 11:21:59 INFO mapreduce.JobSubmitter: Cleaning up the staging area /user/xxxxx/.staging/job_11111111111_1212
Error occured in MapReduce process:
java.io.IOException: Unable to close file because the last block does not have enough number of replicas.
        at org.apache.hadoop.hdfs.DFSOutputStream.completeFile(DFSOutputStream.java:2132)
        at org.apache.hadoop.hdfs.DFSOutputStream.close(DFSOutputStream.java:2100)
        at org.apache.hadoop.fs.FSDataOutputStream$PositionCache.close(FSDataOutputStream.java:70)
        at org.apache.hadoop.fs.FSDataOutputStream.close(FSDataOutputStream.java:103)
        at org.apache.hadoop.io.IOUtils.copyBytes(IOUtils.java:54)
        at org.apache.hadoop.io.IOUtils.copyBytes(IOUtils.java:112)
        at org.apache.hadoop.fs.FileUtil.copy(FileUtil.java:366)
        at org.apache.hadoop.fs.FileUtil.copy(FileUtil.java:338)
        at org.apache.hadoop.fs.FileSystem.copyFromLocalFile(FileSystem.java:1903)
        at org.apache.hadoop.fs.FileSystem.copyFromLocalFile(FileSystem.java:1871)
        at org.apache.hadoop.fs.FileSystem.copyFromLocalFile(FileSystem.java:1836)
        at org.apache.hadoop.mapreduce.JobSubmitter.copyJar(JobSubmitter.java:286)
        at org.apache.hadoop.mapreduce.JobSubmitter.copyAndConfigureFiles(JobSubmitter.java:254)
        at org.apache.hadoop.mapreduce.JobSubmitter.copyAndConfigureFiles(JobSubmitter.java:301)
        at org.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:389)
        at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1285)
        at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1282)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:396)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1594)
        at org.apache.hadoop.mapreduce.Job.submit(Job.java:1282)
        at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:1303)
        at com.xxx.xxx.xxxx.driver.GenerateMyFormat.runMyExtract(GenerateMyFormat.java:222)
        at com.xxx.xxx.xxxx.driver.GenerateMyFormat.run(GenerateMyFormat.java:101)
        at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
        at com.xxx.xxx.xxxx.driver.GenerateMyFormat.main(GenerateMyFormat.java:42)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.apache.hadoop.util.RunJar.main(RunJar.java:212)*

Answer 1

我们有类似的问题。它主要归因于dfs.namenode.handler.count是不够的。增加这可能有助于一些小集群，但这是因为DOS问题，nameNode无法处理否。连接或RPC调用以及待处理的删除块将变得非常庞大。验证hdfs审核日志并查看发生的任何批量删除或其他hdfs操作，并与可能压倒性NN的作业匹配。确定这些任务将有助于HDFS恢复。

无法关闭文件，因为最后一个块没有足够数量的副本

1 个答案: