Hadoop常用命令
启动HDFS集群
[hadoop@hadoop1 ~]$ start-dfs.sh Starting namenodes on [hadoop1] hadoop1: starting namenode, logging to /home/hadoop/apps/hadoop-2.7.5/logs/hadoop-hadoop-namenode-hadoop1.out hadoop2: starting datanode, logging to /home/hadoop/apps/hadoop-2.7.5/logs/hadoop-hadoop-datanode-hadoop2.out hadoop3: starting datanode, logging to /home/hadoop/apps/hadoop-2.7.5/logs/hadoop-hadoop-datanode-hadoop3.out hadoop4: starting datanode, logging to /home/hadoop/apps/hadoop-2.7.5/logs/hadoop-hadoop-datanode-hadoop4.out hadoop1: starting datanode, logging to /home/hadoop/apps/hadoop-2.7.5/logs/hadoop-hadoop-datanode-hadoop1.out Starting secondary namenodes [hadoop3] hadoop3: starting secondarynamenode, logging to /home/hadoop/apps/hadoop-2.7.5/logs/hadoop-hadoop-secondarynamenode-hadoop3.out [hadoop@hadoop1 ~]$
启动YARN集群
[hadoop@hadoop4 ~]$ start-yarn.sh starting yarn daemons starting resourcemanager, logging to /home/hadoop/apps/hadoop-2.7.5/logs/yarn-hadoop-resourcemanager-hadoop4.out hadoop2: starting nodemanager, logging to /home/hadoop/apps/hadoop-2.7.5/logs/yarn-hadoop-nodemanager-hadoop2.out hadoop3: starting nodemanager, logging to /home/hadoop/apps/hadoop-2.7.5/logs/yarn-hadoop-nodemanager-hadoop3.out hadoop4: starting nodemanager, logging to /home/hadoop/apps/hadoop-2.7.5/logs/yarn-hadoop-nodemanager-hadoop4.out hadoop1: starting nodemanager, logging to /home/hadoop/apps/hadoop-2.7.5/logs/yarn-hadoop-nodemanager-hadoop1.out [hadoop@hadoop4 ~]$
查看HDFS系统根目录
[hadoop@hadoop1 ~]$ hadoop fs -ls / Found 2 items drwxr-xr-x - hadoop supergroup 0 2018-03-03 11:42 /test drwx------ - hadoop supergroup 0 2018-03-03 11:42 /tmp [hadoop@hadoop1 ~]$
创建文件夹
[hadoop@hadoop1 ~]$ hadoop fs -mkdir /a [hadoop@hadoop1 ~]$ hadoop fs -ls / Found 3 items drwxr-xr-x - hadoop supergroup 0 2018-03-08 11:09 /a drwxr-xr-x - hadoop supergroup 0 2018-03-03 11:42 /test drwx------ - hadoop supergroup 0 2018-03-03 11:42 /tmp [hadoop@hadoop1 ~]$
级联创建文件夹
[hadoop@hadoop1 ~]$ hadoop fs -mkdir -p /aa/bb/cc [hadoop@hadoop1 ~]$
查看hsdf系统根目录下的所有文件包括子文件夹里面的文件
[hadoop@hadoop1 ~]$ hadoop fs -ls -R /aa
drwxr-xr-x - hadoop supergroup 0 2018-03-08 11:12 /aa/bb
drwxr-xr-x - hadoop supergroup 0 2018-03-08 11:12 /aa/bb/cc
[hadoop@hadoop1 ~]$
上传文件
[hadoop@hadoop1 ~]$ ls
apps data words.txt
[hadoop@hadoop1 ~]$ hadoop fs -put words.txt /aa
[hadoop@hadoop1 ~]$ hadoop fs -copyFromLocal words.txt /aa/bb
[hadoop@hadoop1 ~]$
下载文件
[hadoop@hadoop1 ~]$ hadoop fs -get /aa/words.txt ~/newwords.txt [hadoop@hadoop1 ~]$ ls apps data newwords.txt words.txt [hadoop@hadoop1 ~]$ hadoop fs -copyToLocal /aa/words.txt ~/newwords1.txt [hadoop@hadoop1 ~]$ ls apps data newwords1.txt newwords.txt words.txt [hadoop@hadoop1 ~]$
合并下载
[hadoop@hadoop1 ~]$ hadoop fs -getmerge /aa/words.txt /aa/bb/words.txt ~/2words.txt [hadoop@hadoop1 ~]$ ll 总用量 24 -rw-r--r--. 1 hadoop hadoop 78 3月 8 12:42 2words.txt drwxrwxr-x. 3 hadoop hadoop 4096 3月 3 10:30 apps drwxrwxr-x. 3 hadoop hadoop 4096 3月 3 11:40 data -rw-r--r--. 1 hadoop hadoop 39 3月 8 11:49 newwords1.txt -rw-r--r--. 1 hadoop hadoop 39 3月 8 11:48 newwords.txt -rw-rw-r--. 1 hadoop hadoop 39 3月 3 11:31 words.txt [hadoop@hadoop1 ~]$
复制
从HDFS一个路径拷贝到HDFS另一个路径
[hadoop@hadoop1 ~]$ hadoop fs -ls /a [hadoop@hadoop1 ~]$ hadoop fs -cp /aa/words.txt /a [hadoop@hadoop1 ~]$ hadoop fs -ls /a Found 1 items -rw-r--r-- 2 hadoop supergroup 39 2018-03-08 12:46 /a/words.txt [hadoop@hadoop1 ~]$
移动
在HDFS目录中移动文件
[hadoop@hadoop1 ~]$ hadoop fs -ls /aa/bb/cc [hadoop@hadoop1 ~]$ hadoop fs -mv /a/words.txt /aa/bb/cc [hadoop@hadoop1 ~]$ hadoop fs -ls /aa/bb/cc Found 1 items -rw-r--r-- 2 hadoop supergroup 39 2018-03-08 12:46 /aa/bb/cc/words.txt [hadoop@hadoop1 ~]$
删除
删除文件或文件夹
[hadoop@hadoop1 ~]$ hadoop fs -rm /aa/bb/cc/words.txt 18/03/08 12:49:08 INFO fs.TrashPolicyDefault: Namenode trash configuration: Deletion interval = 0 minutes, Emptier interval = 0 minutes. Deleted /aa/bb/cc/words.txt [hadoop@hadoop1 ~]$ hadoop fs -ls /aa/bb/cc [hadoop@hadoop1 ~]$
删除空目录
[hadoop@hadoop1 ~]$ hadoop fs -rmdir /aa/bb/cc/ [hadoop@hadoop1 ~]$ hadoop fs -ls /aa/bb/ Found 1 items -rw-r--r-- 2 hadoop supergroup 39 2018-03-08 11:43 /aa/bb/words.txt [hadoop@hadoop1 ~]$
强制删除
[hadoop@hadoop1 ~]$ hadoop fs -rm /aa/bb/ rm: `/aa/bb': Is a directory [hadoop@hadoop1 ~]$ hadoop fs -rm -r /aa/bb/ 18/03/08 12:51:31 INFO fs.TrashPolicyDefault: Namenode trash configuration: Deletion interval = 0 minutes, Emptier interval = 0 minutes. Deleted /aa/bb [hadoop@hadoop1 ~]$ hadoop fs -ls /aa Found 1 items -rw-r--r-- 2 hadoop supergroup 39 2018-03-08 11:41 /aa/words.txt [hadoop@hadoop1 ~]$
从本地剪切文件到HDFS上
[hadoop@hadoop1 ~]$ ls apps data hello.txt [hadoop@hadoop1 ~]$ hadoop fs -moveFromLocal ~/hello.txt /aa [hadoop@hadoop1 ~]$ ls apps data [hadoop@hadoop1 ~]$
追加文件
追加之前hello.txt到words.txt之前
[hadoop@hadoop1 ~]$ hadoop fs -appendToFile ~/hello.txt /aa/words.txt [hadoop@hadoop1 ~]$
追加之前hello.txt到words.txt之后
查看文件内容
[hadoop@hadoop1 ~]$ hadoop fs -cat /aa/hello.txt hello hello hello [hadoop@hadoop1 ~]$
chgrp
使用方法：hadoop fs -chgrp [-R] GROUP URI [URI …] Change group association of files. With -R, make the change recursively through the directory structure. The user must be the owner of files, or else a super-user. Additional information is in the Permissions User Guide. -->
改变文件所属的组。使用-R将使改变在目录结构下递归进行。命令的使用者必须是文件的所有者或者超级用户。更多的信息请参见HDFS权限用户指南。
chmod
使用方法：hadoop fs -chmod [-R]
改变文件的权限。使用-R将使改变在目录结构下递归进行。命令的使用者必须是文件的所有者或者超级用户。更多的信息请参见HDFS权限用户指南。
chown
使用方法：hadoop fs -chown [-R] [OWNER][:[GROUP]] URI [URI ]
改变文件的拥有者。使用-R将使改变在目录结构下递归进行。命令的使用者必须是超级用户。更多的信息请参见HDFS权限用户指南。
du
使用方法：hadoop fs -du URI [URI …]
显示目录中所有文件的大小，或者当只指定一个文件时，显示此文件的大小。
示例：
hadoop fs -du /user/hadoop/dir1 /user/hadoop/file1 hdfs://host:port/user/hadoop/dir1
返回值：
成功返回0，失败返回-1。
dus
使用方法：hadoop fs -dus
显示文件的大小。
expunge
使用方法：hadoop fs -expunge
清空回收站。请参考HDFS设计文档以获取更多关于回收站特性的信息。
setrep
使用方法：hadoop fs -setrep [-R]
改变一个文件的副本系数。-R选项用于递归改变目录下所有文件的副本系数。
示例：
- hadoop fs -setrep -w 3 -R /user/hadoop/dir1
返回值：
成功返回0，失败返回-1。
tail
使用方法：hadoop fs -tail [-f] URI
将文件尾部1K字节的内容输出到stdout。支持-f选项，行为和Unix中一致。
示例：
- hadoop fs -tail pathname
返回值：
成功返回0，失败返回-1。
test
使用方法：hadoop fs -test -[ezd] URI
选项：
-e 检查文件是否存在。如果存在则返回0。
-z 检查文件是否是0字节。如果是则返回0。
-d 如果路径是个目录，则返回1，否则返回0。
示例：
-
- hadoop fs -test -e filename
查看集群的工作状态
[hadoop@hadoop1 ~]$ hdfs dfsadmin -report Configured Capacity: 73741402112 (68.68 GB) Present Capacity: 52781039616 (49.16 GB) DFS Remaining: 52780457984 (49.16 GB) DFS Used: 581632 (568 KB) DFS Used%: 0.00% Under replicated blocks: 0 Blocks with corrupt replicas: 0 Missing blocks: 0 Missing blocks (with replication factor 1): 0 ------------------------------------------------- Live datanodes (4): Name: 192.168.123.102:50010 (hadoop1) Hostname: hadoop1 Decommission Status : Normal Configured Capacity: 18435350528 (17.17 GB) DFS Used: 114688 (112 KB) Non DFS Used: 4298661888 (4.00 GB) DFS Remaining: 13193277440 (12.29 GB) DFS Used%: 0.00% DFS Remaining%: 71.57% Configured Cache Capacity: 0 (0 B) Cache Used: 0 (0 B) Cache Remaining: 0 (0 B) Cache Used%: 100.00% Cache Remaining%: 0.00% Xceivers: 1 Last contact: Thu Mar 08 13:05:11 CST 2018 Name: 192.168.123.105:50010 (hadoop4) Hostname: hadoop4 Decommission Status : Normal Configured Capacity: 18435350528 (17.17 GB) DFS Used: 49152 (48 KB) Non DFS Used: 4295872512 (4.00 GB) DFS Remaining: 13196132352 (12.29 GB) DFS Used%: 0.00% DFS Remaining%: 71.58% Configured Cache Capacity: 0 (0 B) Cache Used: 0 (0 B) Cache Remaining: 0 (0 B) Cache Used%: 100.00% Cache Remaining%: 0.00% Xceivers: 1 Last contact: Thu Mar 08 13:05:13 CST 2018 Name: 192.168.123.103:50010 (hadoop2) Hostname: hadoop2 Decommission Status : Normal Configured Capacity: 18435350528 (17.17 GB) DFS Used: 233472 (228 KB) Non DFS Used: 4295700480 (4.00 GB) DFS Remaining: 13196120064 (12.29 GB) DFS Used%: 0.00% DFS Remaining%: 71.58% Configured Cache Capacity: 0 (0 B) Cache Used: 0 (0 B) Cache Remaining: 0 (0 B) Cache Used%: 100.00% Cache Remaining%: 0.00% Xceivers: 1 Last contact: Thu Mar 08 13:05:11 CST 2018 Name: 192.168.123.104:50010 (hadoop3) Hostname: hadoop3 Decommission Status : Normal Configured Capacity: 18435350528 (17.17 GB) DFS Used: 184320 (180 KB) Non DFS Used: 4296941568 (4.00 GB) DFS Remaining: 13194928128 (12.29 GB) DFS Used%: 0.00% DFS Remaining%: 71.57% Configured Cache Capacity: 0 (0 B) Cache Used: 0 (0 B) Cache Remaining: 0 (0 B) Cache Used%: 100.00% Cache Remaining%: 0.00% Xceivers: 1 Last contact: Thu Mar 08 13:05:10 CST 2018 [hadoop@hadoop1 ~]$