實作二： HDFS Shell操作練習
Lab2: HDFS Shell in practice
Lab2: HDFS Shell in practice
前言 Preface
Content 1: HDFS Shell 基本操作
Content 1: Basic HDFS Shell Commands
1.1 瀏覽你HDFS目錄
1.1 Browsing Your HDFS Folder
/opt/hadoop$ bin/hadoop fs -ls /opt/hadoop$ bin/hadoop fs -lsr
1.2 上傳資料到 HDFS 目錄
1.2 Upload Files or Folder to HDFS
- 上傳 Upload
/opt/hadoop$ bin/hadoop fs -put conf input
- 檢查 Check
/opt/hadoop$ bin/hadoop fs -ls /opt/hadoop$ bin/hadoop fs -ls input
1.3 下載 HDFS 的資料到本地目錄
1.3 Download HDFS Files or Folder to Local
- 下載 Download
/opt/hadoop$ bin/hadoop fs -get input fromHDFS
- 檢查 Check
/opt/hadoop$ ls -al | grep fromHDFS /opt/hadoop$ ls -al fromHDFS
1.4 刪除檔案
1.4 Remove Files or Folder
/opt/hadoop$ bin/hadoop fs -ls input /opt/hadoop$ bin/hadoop fs -rm input/masters
1.5 直接看檔案
1.5 Browse Files Directly
/opt/hadoop$ bin/hadoop fs -ls input /opt/hadoop$ bin/hadoop fs -cat input/slaves
1.6 更多指令操作
1.6 More Commands -- Help message
hadooper@vPro:/opt/hadoop$ bin/hadoop fs
Usage: java FsShell
[-ls <path>]
[-lsr <path>]
[-du <path>]
[-dus <path>]
[-count[-q] <path>]
[-mv <src> <dst>]
[-cp <src> <dst>]
[-rm <path>]
[-rmr <path>]
[-expunge]
[-put <localsrc> ... <dst>]
[-copyFromLocal <localsrc> ... <dst>]
[-moveFromLocal <localsrc> ... <dst>]
[-get [-ignoreCrc] [-crc] <src> <localdst>]
[-getmerge <src> <localdst> [addnl]]
[-cat <src>]
[-text <src>]
[-copyToLocal [-ignoreCrc] [-crc] <src> <localdst>]
[-moveToLocal [-crc] <src> <localdst>]
[-mkdir <path>]
[-setrep [-R] [-w] <rep> <path/file>]
[-touchz <path>]
[-test -[ezd] <path>]
[-stat [format] <path>]
[-tail [-f] <file>]
[-chmod [-R] <MODE[,MODE]... | OCTALMODE> PATH...]
[-chown [-R] [OWNER][:[GROUP]] PATH...]
[-chgrp [-R] GROUP PATH...]
[-help [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|jobtracker:port> specify a job tracker
-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]
Content 2: 使用網頁 GUI 瀏覽資訊
Content 2: User Web GUI to browse HDFS
Content 3: 更多 HDFS Shell 的用法
Content 3: More about HDFS Shell
- bin/hadoop fs <args> ，下面則列出 <args> 的用法
Following are the examples of hadoop fs related commands. - 以下操作預設的目錄在 /user/<$username>/ 下
By default, your working directory will be at /user/<$username>/.$ bin/hadoop fs -ls input Found 4 items -rw-r--r-- 2 hadooper supergroup 115045564 2009-04-02 11:51 /user/hadooper/input/1.txt -rw-r--r-- 2 hadooper supergroup 987864 2009-04-02 11:51 /user/hadooper/input/2.txt -rw-r--r-- 2 hadooper supergroup 1573048 2009-04-02 11:51 /user/hadooper/input/3.txt -rw-r--r-- 2 hadooper supergroup 25844527 2009-04-02 11:51 /user/hadooper/input/4.txt
- 完整的路徑則是 hdfs://node:port/path 如：
Or you have to give a absolute path, such as hdfs://node:port/path$ bin/hadoop fs -ls hdfs://gm1.nchc.org.tw:9000/user/hadooper/input Found 4 items -rw-r--r-- 2 hadooper supergroup 115045564 2009-04-02 11:51 /user/hadooper/input/1.txt -rw-r--r-- 2 hadooper supergroup 987864 2009-04-02 11:51 /user/hadooper/input/2.txt -rw-r--r-- 2 hadooper supergroup 1573048 2009-04-02 11:51 /user/hadooper/input/3.txt -rw-r--r-- 2 hadooper supergroup 25844527 2009-04-02 11:51 /user/hadooper/input/4.txt
-cat
- 將路徑指定文件的內容輸出到 STDOUT
Print given file content to STDOUT$ bin/hadoop fs -cat quota/hadoop-env.sh
-chgrp
- 改變文件所屬的組
Change owner group of given file or folder$ bin/hadoop fs -chgrp -R hadooper own
-chmod
- 改變文件的權限
Change read and write permission of given file or folder$ bin/hadoop fs -chmod -R 755 own
-chown
- 改變文件的擁有者
Change owner of given file or folder$ bin/hadoop fs -chown -R hadooper own
-copyFromLocal, -put
- 從 local 放檔案到 hdfs
Both commands will copy given file or folder from local to HDFS$ bin/hadoop fs -put input dfs_input
-copyToLocal, -get
- 把hdfs上得檔案下載到 local
Both commands will copy given file or folder from HDFS to local$ bin/hadoop fs -get dfs_input input1
-cp
- 將文件從 hdfs 原本路徑複製到 hdfs 目標路徑
Copy given file or folder from HDFS source path to HDFS target path$ bin/hadoop fs -cp own hadooper
-du
- 顯示目錄中所有文件的大小
Display the size of files in given folder$ bin/hadoop fs -du input Found 4 items 115045564 hdfs://gm1.nchc.org.tw:9000/user/hadooper/input/1.txt 987864 hdfs://gm1.nchc.org.tw:9000/user/hadooper/input/2.txt 1573048 hdfs://gm1.nchc.org.tw:9000/user/hadooper/input/3.txt 25844527 hdfs://gm1.nchc.org.tw:9000/user/hadooper/input/4.txt
-dus
- 顯示該目錄/文件的總大小
Display total size of given folder$ bin/hadoop fs -dus input hdfs://gm1.nchc.org.tw:9000/user/hadooper/input 143451003
-expunge
- 清空垃圾桶
Clean up Recycled$ bin/hadoop fs -expunge
-getmerge
- 將來源目錄<src>下所有的文件都集合到本地端一個<localdst>檔案內
Merge all files in HDFS source folder <src> into one local file$ bin/hadoop fs -getmerge <src> <localdst>
$ echo "this is one; " >> in1/input $ echo "this is two; " >> in1/input2 $ bin/hadoop fs -put in1 in1 $ bin/hadoop fs -getmerge in1 merge.txt $ cat ./merge.txt
-ls =
- 列出文件或目錄的資訊
List files and folders - 文件名 <副本數> 文件大小 修改日期 修改時間 權限 用戶ID 組ID
<file name> <replication> <size> <modified date> <modified time> <permission> <user id> <group id> - 目錄名 <dir> 修改日期 修改時間 權限 用戶ID 組ID
<folder name> <modified date> <modified time> <permission> <user id> <group id>$ bin/hadoop fs -ls
-lsr
- ls 命令的遞迴版本
list files and folders with recursive$ bin/hadoop fs -lsr /
-mkdir
- 建立資料夾
create directories$ bin/hadoop fs -mkdir a b c
-moveFromLocal
- 將 local 端的資料夾剪下移動到 hdfs 上
move local files or folder to HDFS ( it will delete local files or folder. )$ bin/hadoop fs -moveFromLocal in1 in2
-mv
- 更改資料的名稱
Change file name or folder name.$ bin/hadoop fs -mv in2 in3
-rm
- 刪除指定的檔案（不可資料夾）
Remove given files (not folders)$ bin/hadoop fs -rm in1/input
-rmr
- 遞迴刪除資料夾（包含在內的所有檔案）
Remove given files and folders with recursive$ bin/hadoop fs -rmr in1
-setrep
- 設定副本係數
setup replication numbers of given files or folder$ bin/hadoop fs -setrep [-R] [-w] <rep> <path/file>
$ bin/hadoop fs -setrep -w 2 -R input Replication 2 set: hdfs://gm1.nchc.org.tw:9000/user/hadooper/input/1.txt Replication 2 set: hdfs://gm1.nchc.org.tw:9000/user/hadooper/input/2.txt Replication 2 set: hdfs://gm1.nchc.org.tw:9000/user/hadooper/input/3.txt Replication 2 set: hdfs://gm1.nchc.org.tw:9000/user/hadooper/input/4.txt Waiting for hdfs://gm1.nchc.org.tw:9000/user/hadooper/input/1.txt ... done Waiting for hdfs://gm1.nchc.org.tw:9000/user/hadooper/input/2.txt ... done Waiting for hdfs://gm1.nchc.org.tw:9000/user/hadooper/input/3.txt ... done Waiting for hdfs://gm1.nchc.org.tw:9000/user/hadooper/input/4.txt ... done
-stat
- 印出時間資訊
Print Status of time stamp of folder$ bin/hadoop fs -stat input 2009-04-02 03:51:29
-tail
- 將文件的最後 1K 內容輸出
Display the last 1K contents of given file - 用法 Usage
bin/hadoop fs -tail [-f] 檔案 (-f 參數用來顯示如果檔案增大，則秀出被append上得內容) bin/hadoop fs -tail [-f] <path/file> (-f is used when file had appended)
$ bin/hadoop fs -tail input/1.txt
-test
- 測試檔案， -e 檢查文件是否存在(1=存在, 0＝否)， -z 檢查文件是否為空(1=空, 0＝不為空)， -d 檢查是否為目錄(1=存在, 0＝否)
test files or folders
-e : check if file or folder existed ( 1 = exist , 0 = false )
-z : check if file is empty ( 1 = empty , 0 = false )
-d : check if given path is folder ( 1 = it's folder , 0 = false )- 要用 echo $? 來看回傳值為 0 or 1
You have to use echo $? to get the return value
- 要用 echo $? 來看回傳值為 0 or 1
- 用法 Usage
$ bin/hadoop fs -test -[ezd] URI
$ bin/hadoop fs -test -e /user/hadooper/input/5.txt $ bin/hadoop fs -test -z /user/hadooper/input/5.txt test: File does not exist: /user/hadooper/input/5.txt $ bin/hadoop fs -test -d /user/hadooper/input/5.txt test: File does not exist: /user/hadooper/input/5.txt
-text
- 將檔案（如壓縮檔, textrecordinputstream）輸出為純文字格式
Display archive file contents into STDOUT$ hadoop fs -text <src>
$ hadoop fs -text macadr-eth1.txt.gz 00:1b:fc:61:75:b1 00:1b:fc:58:9c:23
- ps : 目前沒支援zip的函式庫
PS. It does not support zip files yet.$ bin/hadoop fs -text b/a.txt.zip PK ���:��H{ a.txtUT b��Ib��IUx��sssss test PK ���:��H{ ��a.txtUTb��IUxPK@C
-touchz
- 建立一個空文件
creat an empty file$ bin/hadoop fs -touchz b/kk $ bin/hadoop fs -test -z b/kk $ echo $? 1 $ bin/hadoop fs -test -z b/a.txt.zip $ echo $? 0
Last modified 14 years ago
Last modified on Aug 4, 2010, 12:22:16 PM
