Hadoop_04_Hadoop 的HDFS客户端shell命令

1.Hdfs shell客户端命令操作：


1.1.查看命令列表：hadoop fs　

帮助如下：

Usage: hadoop fs [generic options]
        [-appendToFile <localsrc> ... <dst>]   //追加一个文件到已经存在的文件末尾
        [-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>]      //从hdfs剪切粘贴到本地
        [-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 ...]]

Generic options supported are
-conf <configuration file>     specify an application configuration file
-D <property=value>            use value for given property
-fs <local|namenode:port>      specify a namenode
-jt <local|resourcemanager:port>    specify a ResourceManager
-files <comma separated list of files>    specify comma separated files to be copied to the map reduce cluster
-libjars <comma separated list of jars>    specify comma separated jar files to include in the classpath.
-archives <comma separated list of archives>    specify comma separated archives to be unarchived on the compute machines.

The general command line syntax is
bin/hadoop command [genericOptions] [commandOptions]

1.1.1.查看文件列表：hadoop fs　-ls / （/：HDFS文件系统的根目录）

1.1.2.上传文件：hadoop fs -put canglao.avi /

               

　　注意：真实的数据文件路径在DataNode节点数据目录的：/usr/local/src/hadoop-2.6.4/hdpdata3/dfs/data/current/BP-1438427861-192.168.232.201-1529131287527/current/finalized/subdir0/subdir0/下面有如下文件列表：

　　

　　此时会发现在shizhan5的DataNode数据存放目录下面会有该blk_1073741825的副本

　　可以用下面的命令查看一下blk_1073741825文件的内容：cat blk_1073741825

　　然后会发现输出的内容是canglao.avi文件的内容。因为文件太小，没有切开。默认128M才切开，再放一个超过128M的文件：

　　hadoop fs -put /root/temp/hadoop-2.7.3.tar.gz /

　　在dataNode数据存放目录查看（同样存在副本）：

-rw-r--r-- 1 root root     23562  2月 18 12:53 blk_1073741825
-rw-r--r-- 1 root root       195  2月 18 12:53 blk_1073741825_1001.meta
-rw-r--r-- 1 root root 134217728  2月 18 13:09 blk_1073741826
-rw-r--r-- 1 root root   1048583  2月 18 13:09 blk_1073741826_1002.meta
-rw-r--r-- 1 root root  79874467  2月 18 13:09 blk_1073741827
-rw-r--r-- 1 root root    624027  2月 18 13:09 blk_1073741827_1003.meta

　　接下来我们把blk_1073741826和blk_1073741827尝试拼接起来，然后试一下能不能解压：

cat blk_1073741826 >> tmp.file
cat blk_1073741827 >> tmp.file
tar -zxvf tmp.file

　　操作后的文件列表是：

-rw-r--r-- 1 root root     23562  2月 18 12:53 blk_1073741825
-rw-r--r-- 1 root root       195  2月 18 12:53 blk_1073741825_1001.meta
-rw-r--r-- 1 root root 134217728  2月 18 13:09 blk_1073741826
-rw-r--r-- 1 root root   1048583  2月 18 13:09 blk_1073741826_1002.meta
-rw-r--r-- 1 root root  79874467  2月 18 13:09 blk_1073741827
-rw-r--r-- 1 root root    624027  2月 18 13:09 blk_1073741827_1003.meta
drwxr-xr-x 9 root root      4096  8月 18  2016 hadoop-2.7.3/   ----解压tmp.file后的文件
-rw-r--r-- 1 root root 214092195  2月 18 13:16 tmp.file

1.1.3.获取文件：hadoop fs -get /hadoop-2.7.3.tar.gz（完整文件）

1.1.4.删除文件：hadoop fs -rm /canglao.avi


1.1.5.从本地剪切粘贴到HDFS：hadoop fs  -moveFromLocal  /home/hadoop/a.txt  /aaa/bbb

1.1.5.查看集群状态：hdfs dfsadmin -report

[root@shizhan3 subdir0]# hdfs dfsadmin -report
Configured Capacity: 55306051584 (51.51 GB)
Present Capacity: 23346880478 (21.74 GB)
DFS Remaining: 23346765824 (21.74 GB)
DFS Used: 114654 (111.97 KB)
DFS Used%: 0.00%
Under replicated blocks: 0
Blocks with corrupt replicas: 0
Missing blocks: 0

-------------------------------------------------
Live datanodes (3):

Name: 192.168.232.208:50010 (192.168.232.208)
Hostname: shizhan6
Decommission Status : Normal
Configured Capacity: 18435350528 (17.17 GB)
DFS Used: 24576 (24 KB)
Non DFS Used: 10881404928 (10.13 GB)
DFS Remaining: 7553921024 (7.04 GB)
DFS Used%: 0.00%
DFS Remaining%: 40.98%
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: Sat Jun 16 16:44:28 CST 2018

Name: 192.168.232.205:50010 (shizhan3)
Hostname: shizhan3
Decommission Status : Normal
Configured Capacity: 18435350528 (17.17 GB)
DFS Used: 45039 (43.98 KB)
Non DFS Used: 10236620817 (9.53 GB)
DFS Remaining: 8198684672 (7.64 GB)
DFS Used%: 0.00%
DFS Remaining%: 44.47%
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: Sat Jun 16 16:44:27 CST 2018

Name: 192.168.232.207:50010 (shizhan5)
Hostname: shizhan5
Decommission Status : Normal
Configured Capacity: 18435350528 (17.17 GB)
DFS Used: 45039 (43.98 KB)
Non DFS Used: 10841145361 (10.10 GB)
DFS Remaining: 7594160128 (7.07 GB)
DFS Used%: 0.00%
DFS Remaining%: 41.19%
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: Sat Jun 16 16:44:26 CST 2018

 可以看出，集群共有3个datanode可用

 也可以打开web控制台查看HDFS集群信息：http://shizhan2:50070