1.檢視${Hadoop_HOME}/bin/hadoop指令碼的hadoop命令幫助資訊列印可知：

hadoop  version   //檢視版本

hadoop fs        //檔案系統客戶端

hadoop  jar    //執行jar包

hadoop classpath //檢視類路徑

hadoop checknative //檢查本地庫並壓縮

hadoop distcp   // 遠端遞迴拷貝檔案

hadoop credential //認證

hadoop trace    //跟蹤

不同的命令對應了不同的java類

2.bin/hdfs可以執行的命令

dfs                  //等價於 hadoop fs命令.

 classpath            prints the classpath

 namenode -format     format theDFS filesystem

 secondarynamenode    run the DFSsecondary namenode

 namenode             run the DFSnamenode

 journalnode          run the DFSjournalnode

 zkfc                 run the ZKFailover Controller daemon

 datanode             run a DFSdatanode

 dfsadmin             run a DFSadmin client

 haadmin              run a DFS HAadmin client

 fsck                 run a DFSfilesystem checking utility

 balancer             run a clusterbalancing utility

 jmxget               get JMXexported values from NameNode or DataNode.

 mover                run a utilityto move block replicas across

                       storage types

 oiv                  apply theoffline fsimage viewer to an fsimage

 oiv_legacy           apply theoffline fsimage viewer to an legacy fsimage

 oev                  apply theoffline edits viewer to an edits file

 fetchdt              fetch adelegation token from the NameNode

 getconf              get configvalues from configuration

 groups               get thegroups which users belong to

 snapshotDiff         diff twosnapshots of a directory or diff the

                       current directorycontents with a snapshot

 lsSnapshottableDir   list allsnapshottable dirs owned by the current user

                                               Use -help to see options

 portmap              run a portmapservice

 nfs3                 run an NFSversion 3 gateway

 cacheadmin           configure theHDFS cache

 crypto               configureHDFS encryption zones

 storagepolicies      list/get/setblock storage policies

 version              print theversion

3.hdfs fds命令：

Usage: hadoop fs [generic options]

       [-appendToFile <localsrc> ... <dst>]

       [-cat [-ignoreCrc] <src> ...]

       [-checksum <src> ...]

       [-chgrp [-R] GROUP PATH...]

       [-chmod [-R] <MODE[,MODE]... | OCTALMODE> PATH...]

       [-chown [-R] [OWNER][:[GROUP]] PATH...]

       [-copyFromLocal [-f] [-p] [-l] <localsrc> ... <dst>]

       [-copyToLocal [-p] [-ignoreCrc] [-crc] <src> ... <localdst>]

       [-count [-q] [-h] <path> ...]

       [-cp [-f] [-p | -p[topax]] <src> ... <dst>]

       [-createSnapshot <snapshotDir> [<snapshotName>]]

       [-deleteSnapshot<snapshotDir> <snapshotName>]

       [-df [-h] [<path> ...]]

       [-du [-s] [-h] <path> ...]

       [-expunge]

       [-find <path> ... <expression> ...]

       [-get [-p] [-ignoreCrc] [-crc] <src> ... <localdst>]

       [-getfacl [-R] <path>]

       [-getfattr [-R] {-n name | -d} [-e en] <path>]

       [-getmerge [-nl] <src> <localdst>]

       [-help [cmd ...]]

       [-ls [-d] [-h] [-R] [<path> ...]]

       [-mkdir [-p] <path> ...]

       [-moveFromLocal <localsrc> ... <dst>]

       [-moveToLocal <src> <localdst>]

       [-mv <src> ... <dst>]

       [-put [-f] [-p] [-l] <localsrc> ... <dst>]

       [-renameSnapshot <snapshotDir> <oldName> <newName>]

       [-rm [-f] [-r|-R] [-skipTrash] <src> ...]

       [-rmdir [--ignore-fail-on-non-empty] <dir> ...]

       [-setfacl [-R] [{-b|-k} {-m|-x <acl_spec>} <path>]|[--set<acl_spec> <path>]]

       [-setfattr {-n name [-v value] | -x name} <path>]

       [-setrep [-R] [-w] <rep> <path> ...]

       [-stat [format] <path> ...]

       [-tail [-f] <file>]

       [-test -[defsz] <path>]

       [-text [-ignoreCrc] <src> ...]

       [-touchz <path> ...]

       [-truncate [-w] <length> <path> ...]

       [-usage [cmd ...]]

4.例：

$ hdfs dfs -mkdir-p /user/ubuntu/        //在hdfs上建立資料夾

$ hdfs dfs -puthdfs.cmd  /user/ubuntu/  //將本地檔案上傳到HDFS

$ hdfs dfs -get/user/ubuntu/hadoop.cmd  a.cmd   //將檔案從HDFS取回本地

$  hdfs dfs -rm -r  -f  /user/ubuntu/    //刪除

hdfs dfs -ls -R/                       //遞迴展示HDFS檔案系統