HDFS SHELL命令大全

第一个部分为ACL(Access control List)权限

第二个部分为备份数量

第三个部分为所属用户

第四个部分为所属用户组

第五个部分为文件大小[单位：字节]

第六个部分为文件状态stat

第七个部分为文件名称

appendToFile

Usage: hdfsdfs -appendToFile <localsrc> ... <dst>

Appendsingle src, or multiple srcs from local file system to the destination filesystem. Also reads input from stdin and appends to destination file system.

从本地文件系统追加一个或多个文件到hdfs目录；同样能从标准输入读取数据追加到hdfs。

l   hdfsdfs -appendToFile localfile /user/hadoop/hadoopfile

l   hdfsdfs -appendToFile localfile1 localfile2 /user/hadoop/hadoopfile

l   hdfsdfs -appendToFile localfile hdfs://nn.example.com/hadoop/hadoopfile

l   hdfsdfs -appendToFile - hdfs://nn.example.com/hadoop/hadoopfile Reads theinput from stdin.

Exit Code:

Returns0 on success and 1 on error.

cat

Usage: hdfs dfs -cat URI [URI ...]

Copiessource paths to stdout.

Example:

• hdfs dfs -cat hdfs://nn1.example.com/file1 hdfs://nn2.example.com/file2
• hdfs dfs -cat file:///file3 /user/hadoop/file4

ExitCode:

Returns0 on success and -1 on error.

chgrp

Usage: hdfs dfs -chgrp [-R] GROUP URI [URI ...]

Changegroup association of files. The user must be the owner of files, or else asuper-user. Additional information is in the Permissions Guide.

Options

• The -R option will make the change recursively through the directory structure.

chmod

Usage: hdfs dfs -chmod [-R] <MODE[,MODE]... |OCTALMODE> URI [URI ...]

Changethe permissions of files. With -R, make the change recursively through thedirectory structure. The user must be the owner of the file, or else asuper-user. Additional information is in the Permissions Guide.

Options

• The -R option will make the change recursively through the directory structure.

chown

Usage: hdfs dfs -chown [-R] [OWNER][:[GROUP]] URI[URI ]

Changethe owner of files. The user must be a super-user. Additional information is inthe Permissions Guide.

Options

• The -R option will make the change recursively through the directory structure.

copyFromLocal

Usage: hdfs dfs -copyFromLocal <localsrc> URI

Similarto put command, except that the source is restricted to a local file reference.

Options:

• The -f option will overwrite the destination if it already exists.

copyToLocal

Usage: hdfs dfs -copyToLocal [-ignorecrc] [-crc] URI<localdst>

Similarto get command, except that the destination is restricted to a local filereference.

count**

Usage: hdfs dfs -count [-q] [-h] <paths>

Countthe number of directories, files and bytes under the paths that match thespecified file pattern. The output columns with -count are: DIR_COUNT,FILE_COUNT, CONTENT_SIZE FILE_NAME

Theoutput columns with -count -q are: QUOTA, REMAINING_QUATA, SPACE_QUOTA,REMAINING_SPACE_QUOTA, DIR_COUNT, FILE_COUNT, CONTENT_SIZE, FILE_NAME

The-h option shows sizes in human readable format.

Example:

• hdfs dfs -count hdfs://nn1.example.com/file1 hdfs://nn2.example.com/file2
• hdfs dfs -count -q hdfs://nn1.example.com/file1
• hdfs dfs -count -q -h hdfs://nn1.example.com/file1

ExitCode:

Returns0 on success and -1 on error.

cp

Usage: hdfs dfs -cp [-f] [-p | -p[topax]] URI [URI...] <dest>

Copyfiles from source to destination. This command allows multiple sources as wellin which case the destination must be a directory.

'raw.*'namespace extended attributes are preserved if (1) the source and destinationfilesystems support them (HDFS only), and (2) all source and destinationpathnames are in the /.reserved/raw hierarchy. Determination of whether raw.*namespace xattrs are preserved is independent of the -p (preserve) flag.

Options:

• The -f option will overwrite the destination if it already exists.
• The -p option will preserve file attributes [topx] (timestamps, ownership, permission, ACL, XAttr). If -p is specified with no arg, then preserves timestamps, ownership, permission. If -pa is specified, then preserves permission also because ACL is a super-set of permission. Determination of whether raw namespace extended attributes are preserved is independent of the -p flag.

Example:

• hdfs dfs -cp /user/hadoop/file1 /user/hadoop/file2
• hdfs dfs -cp /user/hadoop/file1 /user/hadoop/file2 /user/hadoop/dir

ExitCode:

Returns0 on success and -1 on error.

du

Usage: hdfs dfs -du [-s] [-h] URI [URI ...]

Displayssizes of files and directories contained in the given directory or the lengthof a file in case its just a file.

Options:

• The -s option will result in an aggregate summary of file lengths being displayed, rather than the individual files.
• The -h option will format file sizes in a "human-readable" fashion (e.g 64.0m instead of 67108864)

Example:

• hdfs dfs -du /user/hadoop/dir1 /user/hadoop/file1 hdfs://nn.example.com/user/hadoop/dir1

ExitCode: Returns 0 on success and -1 on error.

dus

Usage: hdfs dfs -dus <args>

Displaysa summary of file lengths.

Note: Thiscommand is deprecated. Instead use hdfs dfs -du -s.

expunge***

Usage: hdfs dfs -expunge

Emptythe Trash.

get

Usage: hdfs dfs -get [-ignorecrc] [-crc] <src><localdst>

Copyfiles to the local file system. Files that fail the CRC check may be copiedwith the -ignorecrc option. Files and CRCs may be copied using the -crc option.

Example:

• hdfs dfs -get /user/hadoop/file localfile
• hdfs dfs -get hdfs://nn.example.com/user/hadoop/file localfile

ExitCode:

Returns0 on success and -1 on error.

getfacl

Usage: hdfs dfs -getfacl[-R] <path>

Displays the Access ControlLists (ACLs) of files and directories. If a directory has a default ACL, thengetfacl also displays the default ACL.

获取目录访问控制列表信息——权限信息

Options:

• -R: List the ACLs of all files and directories recursively.
• path: File or directory to list.

Examples:

• hdfs dfs -getfacl /file
• hdfs dfs -getfacl -R /dir

ExitCode:

Returns0 on success and non-zero on error.

getfattr

Usage: hdfs dfs -getfattr [-R] -n name | -d [-e en] <path>

Displaysthe extended attribute names and values (if any) for a file or directory.

Options:

• -R: Recursively list the attributes for all files and directories.
• -n name: Dump the named extended attribute value.
• -d: Dump all extended attribute values associated with pathname.
• -e encoding: Encode values after retrieving them. Valid encodings are "text", "hex", and "base64". Values encoded as text strings are enclosed in double quotes ("), and values encoded as hexadecimal and base64 are prefixed with 0x and 0s, respectively.
• path: The file or directory.

Examples:

• hdfs dfs -getfattr -d /file
• hdfs dfs -getfattr -R -n user.myAttr /dir

ExitCode:

Returns0 on success and non-zero on error.

getmerge

Usage: hdfs dfs -getmerge <src><localdst> [addnl]

Takesa source directory and a destination file as input and concatenates files insrc into the destination local file. Optionally addnl can be set to enableadding a newline character at the end of each file.

ls

Usage: hdfs dfs -ls [-R] <args>

Options:

• The -R option will return stat recursively through the directory structure.

Fora file returns stat on the file with the following format:

permissions number_of_replicas userid groupid filesize modification_date modification_time filename

Fora directory it returns list of its direct children as in Unix. A directory islisted as:

permissions userid groupid modification_date modification_time dirname

Example:

• hdfs dfs -ls /user/hadoop/file1

ExitCode:

Returns0 on success and -1 on error.

lsr

Usage: hdfs dfs -lsr <args>

Recursiveversion of ls.

Note: Thiscommand is deprecated. Instead use hdfs dfs -ls -R

mkdir

Usage: hdfs dfs -mkdir [-p] <paths>

Takespath uri's as argument and creates directories.

Options:

• The -p option behavior is much like Unix mkdir -p, creating parent directories along the path.

Example:

• hdfs dfs -mkdir /user/hadoop/dir1 /user/hadoop/dir2
• hdfs dfs -mkdir hdfs://nn1.example.com/user/hadoop/dir hdfs://nn2.example.com/user/hadoop/dir

ExitCode:

Returns0 on success and -1 on error.

moveFromLocal

Usage: hdfs dfs -moveFromLocal <localsrc><dst>

Similarto put command, except that the source localsrc is deleted after it's copied.

moveToLocal

Usage: hdfs dfs -moveToLocal [-crc] <src><dst>

Displaysa "Not implemented yet" message.

mv

Usage: hdfs dfs -mv URI [URI ...] <dest>

Movesfiles from source to destination. This command allows multiple sources as wellin which case the destination needs to be a directory. Moving files across filesystems is not permitted.

Example:

• hdfs dfs -mv /user/hadoop/file1 /user/hadoop/file2
• hdfs dfs -mv hdfs://nn.example.com/file1 hdfs://nn.example.com/file2 hdfs://nn.example.com/file3 hdfs://nn.example.com/dir1

ExitCode:

Returns0 on success and -1 on error.

put

Usage: hdfs dfs -put <localsrc> ... <dst>

Copysingle src, or multiple srcs from local file system to the destination filesystem. Also reads input from stdin and writes to destination file system.

• hdfs dfs -put localfile /user/hadoop/hadoopfile
• hdfs dfs -put localfile1 localfile2 /user/hadoop/hadoopdir
• hdfs dfs -put localfile hdfs://nn.example.com/hadoop/hadoopfile
• hdfs dfs -put - hdfs://nn.example.com/hadoop/hadoopfile Reads the input from stdin.

ExitCode:

Returns0 on success and -1 on error.

rm

Usage: hdfs dfs -rm [-f] [-r|-R] [-skipTrash] URI[URI ...]

Deletefiles specified as args.

Options:

• The -f option will not display a diagnostic message or modify the exit status to reflect an error if the file does not exist.
• The -R option deletes the directory and any content under it recursively.
• The -r option is equivalent to -R.
• The -skipTrash option will bypass trash, if enabled, and delete the specified file(s) immediately. This can be useful when it is necessary to delete files from an over-quota directory.

Example:

• hdfs dfs -rm hdfs://nn.example.com/file /user/hadoop/emptydir

ExitCode:

Returns0 on success and -1 on error.

rmr

Usage: hdfs dfs -rmr [-skipTrash] URI [URI ...]

Recursiveversion of delete.

Note: Thiscommand is deprecated. Instead use hdfs dfs -rm -r

setfacl

Usage: hdfs dfs -setfacl [-R] [-b|-k -m|-x <acl_spec> <path>]|[--set <acl_spec><path>]

SetsAccess Control Lists (ACLs) of files and directories.

Options:

• -b: Remove all but the base ACL entries. The entries for user, group and others are retained for compatibility with permission bits.
• -k: Remove the default ACL.
• -R: Apply operations to all files and directories recursively.
• -m: Modify ACL. New entries are added to the ACL, and existing entries are retained.
• -x: Remove specified ACL entries. Other ACL entries are retained.
• --set: Fully replace the ACL, discarding all existing entries. The acl_spec must include entries for user, group, and others for compatibility with permission bits.
• acl_spec: Comma separated list of ACL entries.
• path: File or directory to modify.

Examples:

• hdfs dfs -setfacl -m user:hadoop:rw- /file
• hdfs dfs -setfacl -x user:hadoop /file
• hdfs dfs -setfacl -b /file
• hdfs dfs -setfacl -k /dir
• hdfs dfs -setfacl --set user::rw-,user:hadoop:rw-,group::r--,other::r-- /file
• hdfs dfs -setfacl -R -m user:hadoop:r-x /dir
• hdfs dfs -setfacl -m default:user:hadoop:r-x /dir

ExitCode:

Returns0 on success and non-zero on error.

setfattr

Usage: hdfs dfs -setfattr -nname [-v value] | -x name <path>

Setsan extended attribute name and value for a file or directory.

Options:

• -b: Remove all but the base ACL entries. The entries for user, group and others are retained for compatibility with permission bits.
• -n name: The extended attribute name.
• -v value: The extended attribute value. There are three different encoding methods for the value. If the argument is enclosed in double quotes, then the value is the string inside the quotes. If the argument is prefixed with 0x or 0X, then it is taken as a hexadecimal number. If the argument begins with 0s or 0S, then it is taken as a base64 encoding.
• -x name: Remove the extended attribute.
• path: The file or directory.

Examples:

• hdfs dfs -setfattr -n user.myAttr -v myValue /file
• hdfs dfs -setfattr -n user.noValue /file
• hdfs dfs -setfattr -x user.myAttr /file

ExitCode:

Returns0 on success and non-zero on error.

setrep

Usage: hdfs dfs -setrep [-R] [-w] <numReplicas><path>

Changesthe replication factor of a file. If path isa directory then the command recursively changes the replication factor of allfiles under the directory tree rooted at path.修改文件副本数

Options:

• The -w flag requests that the command wait for the replication to complete. This can potentially take a very long time.
• The -R flag is accepted for backwards compatibility. It has no effect.

Example:

• hdfs dfs -setrep -w 3 /user/hadoop/dir1

ExitCode:

Returns0 on success and -1 on error.

stat

Usage: hdfs dfs -stat URI [URI ...]

Returnsthe stat information on the path.

Example:

• hdfs dfs -stat path

ExitCode: Returns 0 on success and -1 on error.

tail

Usage: hdfs dfs -tail [-f] URI

Displayslast kilobyte[1000字节] of the file to stdout.

Options:

• The -f option will output appended data as the file grows, as in Unix.

Example:

• hdfs dfs -tail pathname

ExitCode: Returns 0 on success and -1 on error.

test

Usage: hdfs dfs -test -[ezd] URI

Options:

• The -e option will check to see if the file exists, returning 0 if true.
• The -z option will check to see if the file is zero length, returning 0 if true.
• The -d option will check to see if the path is directory, returning 0 if true.

Example:

• hdfs dfs -test -e filename

text

Usage: hdfs dfs -text <src>

Takesa source file and outputs the file in text format. The allowed formats are zipand TextRecordInputStream.

touchz

Usage: hdfs dfs -touchz URI [URI ...]

Createa file of zero length.

Example:

• hdfs dfs -touchz pathname

ExitCode: Returns 0 on success and -1 on error.