记载下HDFS的shell操作命令
一、常用命令实操
(0)启动Hadoop集群(方便后续的测试)
start-dfs.sh
start-yarn.sh
(1)-help:输出这个命令参数
hadoop fs -help rm
(2)-ls: 显示目录信息
hadoop fs -ls /
(3)-mkdir:在hdfs上创建目录
hadoop fs -mkdir -p /sanguo/shuguo
(4)-moveFromLocal从本地剪切粘贴到hdfs
hadoop fs -moveFromLocal ./kongming.txt /sanguo/shuguo
(5)–appendToFile :追加一个文件到已经存在的文件末尾
hadoop fs -appendToFile liubei.txt /sanguo/shuguo/kongming.txt
(6)-cat :显示文件内容
hadoop fs -cat /sanguo/shuguo/kongming.txt
(7)-tail:显示一个文件的末尾
hadoop fs -tail /sanguo/shuguo/kongming.txt
(8)-chgrp 、-chmod、-chown:linux文件系统中的用法一样,修改文件所属权限
hadoop fs -chmod 666 /sanguo/shuguo/kongming.txt
(9)-copyFromLocal:从本地文件系统中拷贝文件到hdfs路径去
hadoop fs -copyFromLocal README.txt /
(10)-copyToLocal:从hdfs拷贝到本地
hadoop fs -copyToLocal /sanguo/shuguo/kongming.txt ./
(11)-cp :从hdfs的一个路径拷贝到hdfs的另一个路径
hadoop fs -cp /sanguo/shuguo/kongming.txt /zhuge.txt
(12)-mv:在hdfs目录中移动文件
hadoop fs -mv /zhuge.txt /sanguo/shuguo/
(13)-get:等同于copyToLocal,就是从hdfs下载文件到本地
hadoop fs -get /sanguo/shuguo/kongming.txt ./
(14)-getmerge :合并下载多个文件,比如hdfs的目录 /aaa/下有多个文件:log.1, log.2,log.3,…
hadoop fs -getmerge /user/atguigu/test/* ./zaiyiqi.txt
(15)-put:等同于copyFromLocal
hadoop fs -put ./zaiyiqi.txt /user/atguigu/test/
(16)-rm:删除文件或文件夹
hadoop fs -rm /user/atguigu/test/jinlian2.txt
(17)-rmdir:删除空目录
hadoop fs -rmdir /test
(18)-du统计文件夹的大小信息
hadoop fs -du -h /user/atguigu/test
1.3 K /user/atguigu/test/README.txt
15 /user/atguigu/test/jinlian.txt
1.4 K /user/atguigu/test/zaiyiqi.txt
(19)-setrep:设置hdfs中文件的副本数量
hadoop fs -setrep 10 /sanguo/shuguo/kongming.txt
注:这里设置的副本数只是记录在NameNode的元数据中,是否真的会有这么多副本,还得看DataNode的数量。因为目前只有3台设备,最多也就3个副本,只有节点数的增加到10台时,副本数才能达到10。
附:
bin/hadoop fs
[-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] <localsrc> ... <dst>]
[-copyToLocal [-p] [-ignoreCrc] [-crc] <src> ... <localdst>]
[-count [-q] <path> ...]
[-cp [-f] [-p] <src> ... <dst>]
[-createSnapshot <snapshotDir> [<snapshotName>]]
[-deleteSnapshot <snapshotDir> <snapshotName>]
[-df [-h] [<path> ...]]
[-du [-s] [-h] <path> ...]
[-expunge]
[-get [-p] [-ignoreCrc] [-crc] <src> ... <localdst>]
[-getfacl [-R] <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] <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>]]
[-setrep [-R] [-w] <rep> <path> ...]
[-stat [format] <path> ...]
[-tail [-f] <file>]
[-test -[defsz] <path>]
[-text [-ignoreCrc] <src> ...]
[-touchz <path> ...]
[-usage [cmd ...]]