hadoop有哪些常见错误

这篇文章主要为大家展示了“hadoop有哪些常见错误”,内容简而易懂,条理清晰,希望能够帮助大家解决疑惑,下面让小编带领大家一起研究并学习一下“hadoop有哪些常见错误”这篇文章吧。

网站建设哪家好,找创新互联建站!专注于网页设计、网站建设、微信开发、微信小程序定制开发、集团企业网站建设等服务项目。为回馈新老客户创新互联还提供了恩阳免费建站欢迎大家使用!

1.Got too many exceptions to achieve quorum size 2/3. 3 exceptions thrown:

2016-01-05 23:03:32,967 FATAL org.apache.hadoop.hdfs.server.namenode.FSEditLog: Error: recoverUnfinalizedSegments failed for required journal (JournalAndStream(mgr=QJM to [192.168.10.31:8485, 192.168.10.32:8485, 192.168.10.33:8485], stream=null))
org.apache.hadoop.hdfs.qjournal.client.QuorumException: Got too many exceptions to achieve quorum size 2/3. 3 exceptions thrown:
192.168.10.31:8485: Call From bdata4/192.168.10.34 to bdata1:8485 failed on connection exception: java.net.ConnectException: Connection refused; For more details see:  http://wiki.apache.org/hadoop/ConnectionRefused
192.168.10.33:8485: Call From bdata4/192.168.10.34 to bdata3:8485 failed on connection exception: java.net.ConnectException: Connection refused; For more details see:  http://wiki.apache.org/hadoop/ConnectionRefused
192.168.10.32:8485: Call From bdata4/192.168.10.34 to bdata2:8485 failed on connection exception: java.net.ConnectException: Connection refused; For more details see:  http://wiki.apache.org/hadoop/ConnectionRefused
        at org.apache.hadoop.hdfs.qjournal.client.QuorumException.create(QuorumException.java:81)
        at org.apache.hadoop.hdfs.qjournal.client.QuorumCall.rethrowException(QuorumCall.java:223)
        at org.apache.hadoop.hdfs.qjournal.client.AsyncLoggerSet.waitForWriteQuorum(AsyncLoggerSet.java:142)
        at org.apache.hadoop.hdfs.qjournal.client.QuorumJournalManager.createNewUniqueEpoch(QuorumJournalManager.java:182)
        at org.apache.hadoop.hdfs.qjournal.client.QuorumJournalManager.recoverUnfinalizedSegments(QuorumJournalManager.java:436)
        at org.apache.hadoop.hdfs.server.namenode.JournalSet$8.apply(JournalSet.java:624)
        at org.apache.hadoop.hdfs.server.namenode.JournalSet.mapJournalsAndReportErrors(JournalSet.java:393)
        at org.apache.hadoop.hdfs.server.namenode.JournalSet.recoverUnfinalizedSegments(JournalSet.java:621)
        at org.apache.hadoop.hdfs.server.namenode.FSEditLog.recoverUnclosedStreams(FSEditLog.java:1394)
        at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startActiveServices(FSNamesystem.java:1151)
        at org.apache.hadoop.hdfs.server.namenode.NameNode$NameNodeHAContext.startActiveServices(NameNode.java:1658)
        at org.apache.hadoop.hdfs.server.namenode.ha.ActiveState.enterState(ActiveState.java:61)
        at org.apache.hadoop.hdfs.server.namenode.ha.HAState.setStateInternal(HAState.java:63)
        at org.apache.hadoop.hdfs.server.namenode.ha.StandbyState.setState(StandbyState.java:49)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.transitionToActive(NameNode.java:1536)
        at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.transitionToActive(NameNodeRpcServer.java:1335)
        at org.apache.hadoop.ha.protocolPB.HAServiceProtocolServerSideTranslatorPB.transitionToActive(HAServiceProtocolServerSideTranslatorPB.java:107)
        at org.apache.hadoop.ha.proto.HAServiceProtocolProtos$HAServiceProtocolService$2.callBlockingMethod(HAServiceProtocolProtos.java:4460)
        at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:619)
        at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:962)
        at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2040)
        at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2036)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:415)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1656)
        at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2034)

2016-01-05 23:03:32,968 INFO org.apache.hadoop.util.ExitUtil: Exiting with status 1

错误原因:

我们在执行start-dfs.sh的时候,默认启动顺序是namenode>datanode>journalnode>zkfc,如果journalnode和namenode不在一台机器启动的话,很容易因为网络延迟问题导致NN无法连接JN,无法实现选举,最后导致刚刚启动的namenode会突然挂掉一个主的,留下一个standy的,虽然有NN启动时有重试机制等待JN的启动,但是由于重试次数限制,可能网络情况不好,导致重试次数用完了,也没有启动成功,

A:此时需要手动启动主的那个namenode,避免了网络延迟等待journalnode的步骤,一旦两个namenode连入journalnode,实现了选举,则不会出现失败情况,

B:先启动JournalNode然后再运行start-dfs.sh,

C:把nn对jn的容错次数或时间调成更大的值,保证能够对正常的启动延迟、网络延迟能容错

在hdfs-site.xml中加入,nn对jn检测的重试次数,默认为10次,每次1000ms,故网络情况差需要增加,这里设置为30次

   
         ipc.client.connect.max.retries
         30

   

2、org.apache.hadoop.security.AccessControlException: Permission denied

在master节点上修改hdfs-site.xml加上以下内容 

 

dfs.permissions 

false 

 

旨在取消权限检查,原因是为了解决我在windows机器上配置eclipse连接hadoop服务器时,配置map/reduce连接后报错

3、运行报:[org.apache.hadoop.security.ShellBasedUnixGroupsMapping]-[WARN] got exception trying to get groups for user bdata

在master节点上修改hdfs-site.xml加上以下内容


dfs.web.ugi
bdata,supergroup

以上是“hadoop有哪些常见错误”这篇文章的所有内容,感谢各位的阅读!相信大家都有了一定的了解,希望分享的内容对大家有所帮助,如果还想学习更多知识,欢迎关注创新互联行业资讯频道!


当前标题:hadoop有哪些常见错误
文章路径:http://myzitong.com/article/ppgoho.html