Hadoop常见异常及其解决方式
1、Shell$ExitCodeException
现象：执行hadoop job时出现例如以下异常：
14/07/09 14:42:50 INFO mapreduce.Job: Task Id : attempt_1404886826875_0007_m_000000_1, Status : FAILED
Exception from container-launch: org.apache.hadoop.util.Shell$ExitCodeException:
org.apache.hadoop.util.Shell$ExitCodeException:
at org.apache.hadoop.util.Shell.runCommand(Shell.java:505)
at org.apache.hadoop.util.Shell.run(Shell.java:418)
at org.apache.hadoop.util.Shell$ShellCommandExecutor.execute(Shell.java:650)
at org.apache.hadoop.yarn.server.nodemanager.DefaultContainerExecutor.launchContainer(DefaultContainerExecutor.java:195)
at org.apache.hadoop.yarn.server.nodemanager.containermanager.launcher.ContainerLaunch.call(ContainerLaunch.java:300)
at org.apache.hadoop.yarn.server.nodemanager.containermanager.launcher.ContainerLaunch.call(ContainerLaunch.java:81)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:744)
Container exited with a non-zero exit code 1
原因及解决的方法：原因未知。
重新启动可恢复正常
2、libhadoop.so.1.0.0 which might have disabled stack guard
现象：Hadoop 2.2.0 - warning: You have loaded library /home/hadoop/2.2.0/lib/native/libhadoop.so.1.0.0 which might have disabled stack guard.
export PATH=$PATH:/home/jediael/hadoop-2.4.1/bin:/home/jediael/hadoop-2.4.1/sbin
export HADOOP_HOME=/home/jediael/hadoop-2.4.1
export HADOOP_COMMON_HOME=$HADOOP_HOME
export HADOOP_HDFS_HOME=$HADOOP_HOME
export HADOOP_MAPRED_HOME=$HADOOP_HOME
export HADOOP_YARN_HOME=$HADOOP_HOME
export HADOOP_CONF_DIR=$HADOOP_HOME/etc/hadoop
export HADOOP_COMMON_LIB_NATIVE_DIR=$HADOOP_HOME/lib/native
export HADOOP_OPTS="-Djava.library.path=$HADOOP_HOME/lib"
3、Retrying connect to server: master166/10.252.48.166:9000. Already tried 0 time(s)
在datanode上运行hdfs相关命令时，出现下面错误：
[jediael@slave156 ~]$ hadoop fs -ls /
14/08/31 15:00:37 INFO ipc.Client: Retrying connect to server: master166/10.252.48.166:9000. Already tried 0 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/08/31 15:00:38 INFO ipc.Client: Retrying connect to server: master166/10.252.48.166:9000. Already tried 1 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/08/31 15:00:39 INFO ipc.Client: Retrying connect to server: master166/10.252.48.166:9000. Already tried 2 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/08/31 15:00:40 INFO ipc.Client: Retrying connect to server: master166/10.252.48.166:9000. Already tried 3 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/08/31 15:00:41 INFO ipc.Client: Retrying connect to server: master166/10.252.48.166:9000. Already tried 4 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/08/31 15:00:42 INFO ipc.Client: Retrying connect to server: master166/10.252.48.166:9000. Already tried 5 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/08/31 15:00:43 INFO ipc.Client: Retrying connect to server: master166/10.252.48.166:9000. Already tried 6 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/08/31 15:00:44 INFO ipc.Client: Retrying connect to server: master166/10.252.48.166:9000. Already tried 7 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/08/31 15:00:45 INFO ipc.Client: Retrying connect to server: master166/10.252.48.166:9000. Already tried 8 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
14/08/31 15:00:46 INFO ipc.Client: Retrying connect to server: master166/10.252.48.166:9000. Already tried 9 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS)
ls: Call to master166/10.252.48.166:9000 failed on connection exception: java.net.ConnectException: Connection refused
出现以上错误，通常都是因为datanode无法连接到namenode所致，下面是一种情况：
/etc/hosts中存在127.0.0.1 *****的配置，如
127.0.0.1 localhost
将这些配置去掉，然后又一次格式化namenode。并重新启动hadoop进程就可以解决。
或者是下面原因：
hadoop安装完毕后，必需要用haddop namenode format格式化后，才干使用，假设重新启动机器
在启动hadoop后，用hadoop fs -ls命令老是报 10/09/25 18:35:29 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 0 time(s).的错误，
用jps命令。也看不不到namenode的进程。 必须再用命令hadoop namenode format格式化后。才干再使用
原因是：hadoop默认配置是把一些tmp文件放在/tmp文件夹下，重新启动系统后，tmp文件夹下的东西被清除。所以报错
解决方法：在conf/core-site.xml 中添加下面内容
<property>
<name>hadoop.tmp.dir</name>
<value>/var/log/hadoop/tmp</value>
<description>A base for other temporary directories</description>
</property>
重新启动hadoop后，格式化namenode就可以
4、Permission denied: user=liaoliuqing, access=WRITE, inode="":jediael:supergroup:rwxr-xr-x
原由于用户权限不足，能能訪写HDFS中的文件。
解决方式：
关闭hadoop权限。在hdfs-site.xml文件里加入
<property>
<name>dfs.permissions</name>
<value>false</value>
</property>
5、Incompatible namespaceIDs
2015-02-02 15:10:57,526 INFO org.apache.hadoop.metrics2.impl.MetricsConfig: loaded properties from hadoop-metrics2.properties
2015-02-02 15:10:57,543 INFO org.apache.hadoop.metrics2.impl.MetricsSourceAdapter: MBean for source MetricsSystem,sub=Stats registered.
2015-02-02 15:10:57,543 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: Scheduled snapshot period at 10 second(s).
2015-02-02 15:10:57,544 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: DataNode metrics system started
2015-02-02 15:10:57,699 INFO org.apache.hadoop.metrics2.impl.MetricsSourceAdapter: MBean for source ugi registered.
2015-02-02 15:10:58,090 ERROR org.apache.hadoop.hdfs.server.datanode.DataNode: java.io.IOException: Incompatible namespaceIDs in /mnt/tmphadoop/dfs/data: namenode namespaceID = 2017454015; datanode namespaceID = 1238467850
at org.apache.hadoop.hdfs.server.datanode.DataStorage.doTransition(DataStorage.java:232)
at org.apache.hadoop.hdfs.server.datanode.DataStorage.recoverTransitionRead(DataStorage.java:147)
at org.apache.hadoop.hdfs.server.datanode.DataNode.startDataNode(DataNode.java:414)
at org.apache.hadoop.hdfs.server.datanode.DataNode.<init>(DataNode.java:321)
at org.apache.hadoop.hdfs.server.datanode.DataNode.makeInstance(DataNode.java:1712)
at org.apache.hadoop.hdfs.server.datanode.DataNode.instantiateDataNode(DataNode.java:1651)
at org.apache.hadoop.hdfs.server.datanode.DataNode.createDataNode(DataNode.java:1669)
at org.apache.hadoop.hdfs.server.datanode.DataNode.secureMain(DataNode.java:1795)
at org.apache.hadoop.hdfs.server.datanode.DataNode.main(DataNode.java:1812)
问题原因：
每次namenode format会又一次创建一个namenodeId,而${hadoop.tmp.dir}/dfs/data下包括了上次format下的id,当又一次运行namenode format时清空了namenode下的数据,可是没有清空datanode下的数据,所以造成namenode节点上的namespaceID与 datanode节点上的namespaceID不一致，从而导致从现上述异常，启动失败。
解决的方法：
（1）停止hadoop
stop-all.sh
（2）在各个slave中删除dfs.data.dir中的内容。
若此属性未改动。则其默认值为
<property>
<name>${dfs.data.dir}</name>
<value>${hadoop.tmp.dir}/dfs/data</value>
<description>Determines where on the local filesystem an DFS data node
should store its blocks. If this is a comma-delimited
list of directories, then data will be stored in all named
directories, typically on different devices.
Directories that do not exist are ignored.
</description>
</property>
（3）又一次格式化namenode
hadoop namenode -format
然后start-all.sh启动hadoop
以上解决的方法须要将原有数据删除，若数据不能删除。则使用下面方法之中的一个：
（1）改动${dfs.data.dir}/current/VERSION文件。将datanode中的id改成与namenode中的id一致。
（2）改动${dfs.data.dir}
