Hadoop 2.6.0：安装后基本错误“正在启动 MRAppMaster”

Question

我刚刚开始使用 Hadoop 2。

使用基本配置安装后，我总是无法运行任何示例。有没有人看到这个问题，请帮助我？

错误类似于

Error starting MRAppMaster
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException

这是日志

20152015-01-06 11:56:23,194 INFO [main] org.apache.hadoop.mapreduce.v2.app.MRAppMaster: Created MRAppMaster for application appattempt_1420510526926_0002_000001
2015-01-06 11:56:23,362 FATAL [main] org.apache.hadoop.mapreduce.v2.app.MRAppMaster: Error starting MRAppMaster

java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:131)
at org.apache.hadoop.security.Groups.<init>(Groups.java:70)
at org.apache.hadoop.security.Groups.<init>(Groups.java:66)
at org.apache.hadoop.security.Groups.getUserToGroupsMappingService(Groups.java:280)
at org.apache.hadoop.security.UserGroupInformation.initialize(UserGroupInformation.java:271)
at org.apache.hadoop.security.UserGroupInformation.setConfiguration(UserGroupInformation.java:299)
at org.apache.hadoop.mapreduce.v2.app.MRAppMaster.initAndStartAppMaster(MRAppMaster.java:1473)
at org.apache.hadoop.mapreduce.v2.app.MRAppMaster.main(MRAppMaster.java:1429)

Caused by: java.lang.reflect.InvocationTargetException
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.util.ReflectionUtils.newInstance(ReflectionUtils.java:129)
... 7 more

Caused by: java.lang.UnsatisfiedLinkError: org.apache.hadoop.security.JniBasedUnixGroupsMapping.anchorNative()V
at org.apache.hadoop.security.JniBasedUnixGroupsMapping.anchorNative(Native Method)
at org.apache.hadoop.security.JniBasedUnixGroupsMapping.<clinit>(JniBasedUnixGroupsMapping.java:49)
at org.apache.hadoop.security.JniBasedUnixGroupsMappingWithFallback.<init>(JniBasedUnixGroupsMappingWithFallback.java:39)
... 12 more

2015-01-06 11:56:23,366 INFO [main] org.apache.hadoop.util.ExitUtil: Exiting with status 1

Answer 1

错误消息：“错误启动 MRAppMaster”、“InvocationTargetException”、“UnsatisfiedLinkError”

根本原因：无法执行“org.apache.hadoop.security.JniBasedUnixGroupsMapping”类中的原生函数“anchorNative”

说明：函数“anchorNative”将调用库“libhadoop.so”中的函数。这个库的路径由这些环境变量指定：

export JAVA_LIBRARY_PATH
export HADOOP_COMMON_LIB_NATIVE_DIR

在Hadoop源码中，通过

打印java库类路径

System.err.println( (System.getProperty("java.library.path") );

# result
/home/maidinh/hadoop2/build/hadoop-2.6.0-src/hadoop-dist/target/hadoop-2.6.0/lib/native:
/usr/java/packages/lib/amd64:
/usr/lib64:
/lib64:
/lib:
/usr/lib

库“libhadoop.so”的不同版本可以在这些产生冲突的位置找到。

解决方法：除了native库的正确路径（在hadoop-2.6.0/lib/native中），删除其他目录下的所有“libhadoop.so”。

注意事项：删除hadoop的所有相关库

rm -r libhadoop*
rm -r libhdfs*