这玩意儿第一次弄太坑了… 必须记录一下
cd到$HADOOP_HOME下（/usr/local/hadoop (如果没有就先source /etc/profile
在改目录下创建wcinput和word.txt 并输入你喜欢的内容hhh
source /etc/profile cd $HADOOP_HOME mkdir wcinput vim wcinput/word.txt
然后执行wordcount报错
[root@node01 hadoop]# bin/hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-3.2.3.jar wordcount wcinput/ ./wcoutput WARNING: HADOOP_PREFIX has been replaced by HADOOP_HOME. Using value of HADOOP_PREFIX. 2022-06-22 06:36:26,056 INFO client.RMProxy: Connecting to ResourceManager at node01/172.18.0.2:8032 2022-06-22 06:36:26,325 INFO mapreduce.JobResourceUploader: Disabling Erasure Coding for path: /tmp/hadoop-yarn/staging/root/.staging/job_1655879060022_0002 2022-06-22 06:36:26,481 INFO mapreduce.JobSubmitter: Cleaning up the staging area /tmp/hadoop-yarn/staging/root/.staging/job_1655879060022_0002 org.apache.hadoop.mapreduce.lib.input.InvalidInputException: Input path does not exist: hdfs://node01:9000/user/root/wcinput at org.apache.hadoop.mapreduce.lib.input.FileInputFormat.singleThreadedListStatus(FileInputFormat.java:332) at org.apache.hadoop.mapreduce.lib.input.FileInputFormat.listStatus(FileInputFormat.java:274) at org.apache.hadoop.mapreduce.lib.input.FileInputFormat.getSplits(FileInputFormat.java:396) at org.apache.hadoop.mapreduce.JobSubmitter.writeNewSplits(JobSubmitter.java:310) at org.apache.hadoop.mapreduce.JobSubmitter.writeSplits(JobSubmitter.java:327) at org.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:200) at org.apache.hadoop.mapreduce.Job$11.run(Job.java:1565) at org.apache.hadoop.mapreduce.Job$11.run(Job.java:1562) at java.security.AccessController.doPrivileged(Native Method) at javax.security.auth.Subject.doAs(Subject.java:422) at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1762) at org.apache.hadoop.mapreduce.Job.submit(Job.java:1562) at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:1583) at org.apache.hadoop.examples.WordCount.main(WordCount.java:87) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.apache.hadoop.util.ProgramDriver$ProgramDescription.invoke(ProgramDriver.java:71) at org.apache.hadoop.util.ProgramDriver.run(ProgramDriver.java:144) at org.apache.hadoop.examples.ExampleDriver.main(ExampleDriver.java:74) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.apache.hadoop.util.RunJar.run(RunJar.java:323) at org.apache.hadoop.util.RunJar.main(RunJar.java:236)
开始实在不理解为什么我的node01是8032然后又给我映射到9000去，看了很多博客也尝试了很多办法
最后关注报错中这句 Input path does not exist: hdfs://node01:9000/user/root/wcinput
所以实际应该是把文件放到hdfs里，其实也就只有这样，才能让文件被所有节点访问
hdfs dfs -mkdir -p /user/root/wcinput/ hdfs dfs -put wcinput/word.txt /user/root/wcinput/
然后再MapReduce，注意是在$HADOOP_HOME下执行的
bin/hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-3.2.3.jar wordcount wcinput/ ./wcoutput
查看结果：
hdfs dfs -cat /user/root/wcoutput/part-r-00000
可管理界面查看：http://localhost:8088
