一个Hadoop难以查找的错误
This script is Deprecated. Instead use start-dfs.sh and start-yarn.sh
Starting namenodes on [Master132.Hadoop]
Master132.Hadoop: starting namenode, logging to /usr/hadoop/logs/hadoop-hadoop-namenode-Master132.Hadoop.out
Slave110.Hadoop: /usr/hadoop/sbin/hadoop-daemon.sh: line 69: [: .out: integer expression expected
Slave110.Hadoop: starting datanode, logging to /usr/hadoop/logs/hadoop-hadoop-datanode-Slave110.Hadoop
Slave131.Hadoop: starting datanode, logging to /usr/hadoop/logs/hadoop-hadoop-datanode-Slave131.Hadoop.out
Slave141.Hadoop: starting datanode, logging to /usr/hadoop/logs/hadoop-hadoop-datanode-Slave141.Hadoop.out
Slave110.Hadoop: Exception in thread "main" Java.lang.NoClassDefFoundError: /log
Slave110.Hadoop: Caused by: java.lang.ClassNotFoundException: .log
Slave110.Hadoop: at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
Slave110.Hadoop: at java.security.AccessController.doPrivileged(Native Method)
Slave110.Hadoop: at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
Slave110.Hadoop: at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
Slave110.Hadoop: at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
Slave110.Hadoop: at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
Slave110.Hadoop: Could not find the main class: .log. Program will exit.
Starting secondary namenodes [Master132.Hadoop]
Master132.Hadoop: starting secondarynamenode, logging to /usr/hadoop/logs/hadoop-hadoop-secondarynamenode-Master132.Hadoop.out
starting yarn daemons
starting resourcemanager, logging to /usr/hadoop/logs/yarn-hadoop-resourcemanager-Master132.Hadoop.out
Slave110.Hadoop: /usr/hadoop/sbin/yarn-daemon.sh: line 72: [: .out: integer expression expected
Slave110.Hadoop: starting nodemanager, logging to /usr/hadoop/logs/yarn-hadoop-nodemanager-Slave110.Hadoop
Slave131.Hadoop: starting nodemanager, logging to /usr/hadoop/logs/yarn-hadoop-nodemanager-Slave131.Hadoop.out
Slave141.Hadoop: starting nodemanager, logging to /usr/hadoop/logs/yarn-hadoop-nodemanager-Slave141.Hadoop.out
Slave110.Hadoop: Exception in thread "main" java.lang.NoClassDefFoundError: /log
Slave110.Hadoop: Caused by: java.lang.ClassNotFoundException: .log
Slave110.Hadoop: at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
Slave110.Hadoop: at java.security.AccessController.doPrivileged(Native Method)
Slave110.Hadoop: at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
Slave110.Hadoop: at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
Slave110.Hadoop: at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
Slave110.Hadoop: at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
Slave110.Hadoop: Could not find the main class: .log. Program will exit.
周末，原本搭建好的Hadoop集群在启动中突然报出以上的错误！一个节点不好用了！经过了各种查找，还是没有解决。
今天终于查到原因了！datenode节点Slave110.Hadoop的主机名后面不知道什么时候添加了一个空格！删除就好了！崩溃
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