Oracle® Database Utilities 10g Release 2 (10.2) Part Number B14215-01 |
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This chapter describes the Automatic Storage Management Command-Line Utility (ASMCMD). It contains the following topics:
ASMCMD is a command-line utility that you can use to easily view and manipulate files and directories within Automatic Storage Management (ASM) disk groups. It can list the contents of disk groups, perform searches, create and remove directories and aliases, display space utilization, and more.
Note:
You cannot use ASMCMD to create or drop disk groups or to add or drop disks in a disk group. For these operations, you must use SQL commands.See Also:
Oracle Database Administrator's Guide for general information on Automatic Storage Management.ASMCMD works with Automatic Storage Management (ASM) files, directories, and aliases. Before using ASMCMD, you must understand how these common computing concepts apply to the unique ASM environment. The following are some key definitions.
Note:
The forward slash (/) and backward slash (\) are interchangeable in filenames. Also, filenames are case insensitive, but case retentive.System-generated filename or 'fully qualified filename'
Every file created in ASM gets a system-generated filename, otherwise known as a fully qualified filename. This is analogous to a complete path name in a local file system. An example of a fully qualified filename is the following:
+dgroup2/sample/controlfile/Current.256.541956473
ASM generates filenames according to the following scheme:
+diskGroupName/databaseName/fileType/fileTypeTag.file.incarnation
In the previous fully qualified filename, dgroup2
is the disk group name, sample
is the database name, controlfile
is the file type, and so on.
See Oracle Database Administrator's Guide for more detailed information on fully qualified filenames.
Directory
As in other file systems, an ASM directory is a container for files, and it can be part of a tree structure of other directories.
The fully qualified filename in fact represents a hierarchy of directories, with the plus sign (+) as the root. In each disk group, ASM creates a directory hierarchy that corresponds to the structure of the fully qualified filenames in the disk group. The directories in this hierarchy are known as system-generated directories. ASMCMD enables you to move up and down this directory hierarchy with the cd
(change directory) command. The ASMCMD ls
(list directory) command lists the contents of the current directory, while the pwd
command prints the name of the current directory.
When you start ASMCMD, the current directory is set to root (+). For an ASM instance with two disk groups, dgroup1
and dgroup2
, entering an ls
command with the root directory as the current directory produces the following output:
ASMCMD> ls DGROUP1/ DGROUP2/
The following example demonstrates navigating the ASM directory tree (refer to the fully qualified filename shown previously):
ASMCMD> cd +dgroup1/sample/controlfile ASMCMD> ls Current.256.541956473 Current.257.541956475
You can also create your own directories as subdirectories of the system-generated directories. You do so with the ALTER DISKGROUP
command or with the ASMCMD mkdir
command. Your user-created directories can have subdirectories, and you can navigate the hierarchy of both system-generated directories and user-generated directories with the cd
command. See Oracle Database Administrator's Guide for more information on ASM directories.
The following example creates the directory mydir
in the disk group dgroup1
:
ASMCMD> mkdir +dgroup1/mydir
(Note that the directory dgroup1
is a system-generated directory. Its contents represent the contents of the disk group dgroup1
.)
If you start ASMCMD with the -p
flag, ASMCMD always shows the current directory as part of its prompt.
ASMCMD [+] > cd dgroup1/mydir ASMCMD [+DGROUP1/MYDIR] >
Note:
ASM does not place system-generated files into your user-created directories; it places them only in system-generated directories. You add aliases (described next) or other directories to a user-created directory.Alias
An alias is a filename that is a reference (or pointer) to a system-generated filename, but with a more user-friendly name. It is similar to a symbolic link in Unix operating systems. You create aliases to make it easier to work with ASM filenames. You can create an alias with an ALTER DISKGROUP
command or with the mkalias
ASMCMD command.
An alias has at a minimum the disk group name as part of its complete path. You can create aliases at the disk group level or in any system-generated or user-created subdirectory. The following are examples of aliases:
+dgroup1/ctl1.f +dgroup1/sample/ctl1.f +dgroup1/mydir/ctl1.f
If you run the ASMCMD ls
(list directory) with the -l
flag, each alias is listed with the system-generated file that it references.
ctl1.f => +dgroup2/sample/controlfile/Current.256.541956473
See Oracle Database Administrator's Guide for more information on aliases.
Absolute path and Relative path
When you run an ASMCMD command that takes a filename or directory name as an argument, you can supply the name as either an absolute path or a relative path.
An absolute path refers to the full path to a file or directory. An absolute path begins with a plus sign (+), followed by a disk group name, followed by subsequent directories in the directory tree until the file or directory of interest is reached. A complete system-generated filename (otherwise known as the fully qualified filename) is an example of an absolute path to a file.
Using an absolute path enables the command to access the file or directory regardless of where the current directory is set. The following rm
command uses an absolute path for the filename:
ASMCMD [+DGROUP1/MYDIR] > rm +dgroup2/sample/datafile/users.259.555341963
The following command uses an absolute path to the directory.
ASMCMD [+DGROUP1/MYDIR] > cd +dgroup2/sample/controlfile
A relative path includes only the part of the filename or directory name that is not part of the current directory. That is, the path to the file or directory is relative to the current directory.
In the following example, the rm
command operates on the file undotbs1.272.557429239
, which in this case is a relative path. ASMCMD prepends the current directory to the command argument to obtain the absolute path to the file, which is +dgroup1/sample/datafile/undotbs1.272.557429239
.
ASMCMD [+] > cd +dgroup1 ASMCMD [+DGROUP1] > cd sample/datafile ASMCMD [+DGROUP1/SAMPLE/DATAFILE] > ls EXAMPLE.269.555342243 SYSAUX.257.555341961 SYSTEM.256.555341961 UNDOTBS1.258.555341963 UNDOTBS1.272.557429239 USERS.259.555341963 ASMCMD [+DGROUP1/SAMPLE/DATAFILE] > rm undotbs1.272.557429239
Paths to directories can also be relative. You can go up or down the hierarchy of the current directory tree branch by providing a directory argument to the cd
(change directory) command whose path is relative to the current directory.
In addition, you can use the pseudo-directories "." and ".." in place of a directory name. The "." pseudo-directory is the current directory. The ".." psuedo-directory is the parent directory of the current directory.
The following example demonstrates using relative directory paths and pseudo-directories:
ASMCMD [+DGROUP1/SAMPLE] > cd datafile ASMCMD [+DGROUP1/SAMPLE/DATAFILE] >cd .. ASMCMD [+DGROUP1/SAMPLE] >
Wildcard
The wildcard characters "*" and "%" match zero or more characters anywhere within an absolute or relative path. The two characters behave identically. The ASMCMD commands that accept wildcards are ls
, du
, rm
, and find
. The following examples illustrate the use of wildcards.
ASMCMD> ls +dgroup1/mydir1 ctl.f data1.f dummy.f ASMCMD> ls +dgroup1/mydir1/d* data1.f dummy.f ASMCMD> ls +group1/sample/* +dgroup1/sample/CONTROLFILE/: Current.260.555342185 Current.261.555342183 +dgroup1/sample/DATAFILE/: EXAMPLE.269.555342243 SYSAUX.257.555341961 SYSTEM.256.555341961 UNDOTBS1.272.557429239 USERS.259.555341963 +dgroup1/sample/ONLINELOG/: group_1.262.555342191 group_1.263.555342195 group_2.264.555342197 group_2.265.555342201 +dgroup1/sample/PARAMETERFILE/: spfile.270.555342443 +dgroup1/sample/TEMPFILE/: TEMP.268.555342229
You can run the ASMCMD utility in either interactive or noninteractive mode. Before running ASMCMD, you must ensure that you are logged in properly and that your environment is properly configured.
To prepare to run ASMCMD:
Ensure that the ASM instance is started and the ASM disk groups are mounted. (You cannot use ASMCMD to mount disk groups.)
Log in to the host that is running the ASM instance that you want to work with. You must log in as a user that has SYSDBA
privileges through operating system authentication.
See Oracle Database Administrator's Guide for information on operating system authentication.
Set the ORACLE_HOME
and ORACLE_SID
environment variables to select the ASM instance. Depending on your operating system, you may have to set other environment variables to properly connect to the ASM instance. See Oracle Database Administrator's Guide for more information on setting environment variables.
The default value of the ASM SID for a single instance database is +ASM
. On a Real Application Clusters system, the default value of the ASM SID on any node is +ASM
node#
.
Ensure that bin
subdirectory of your Oracle home is in your PATH
environment variable.
The interactive mode of the ASMCMD utility provides a shell-like environment where you are prompted to enter ASMCMD commands.
To run ASMCMD in interactive mode:
At the operating system command prompt, enter:
asmcmd
An ASMCMD command prompt is displayed.
ASMCMD>
Enter an ASMCMD command and press the Enter
key.
The command runs and displays its output, if any, and then ASMCMD prompts for the next command.
Continue entering ASMCMD commands. Enter the command exit
to exit ASMCMD.
Including the Current Directory in the ASMCMD Prompt
You can specify the -p
option with the asmcmd
command to include the current directory in the ASMCMD prompt, as shown in the following example:
% asmcmd -p ASMCMD [+] > cd dgroup1/mydir ASMCMD [+DGROUP1/MYDIR] >
In noninteractive mode, you run a single ASMCMD command by including the command and command arguments on the command line that invokes ASMCMD. ASMCMD runs the command, generates output if any, and then exits. The noninteractive mode is especially useful for running scripts.
To run ASMCMD in noninteractive mode:
At the command prompt, enter:
asmcmd
command
arguments
where:
command
is any valid ASMCMD command. arguments
is a list of command flags and arguments.
The following example demonstrates running ASMCMD in the noninteractive mode.
% asmcmd ls -l State Type Rebal Unbal Name MOUNTED NORMAL N N DGROUP1/ MOUNTED NORMAL N N DGROUP2/ %
This section describes each individual ASMCMD command in detail. Table 20-1 provides a summary of all ASMCMD commands.
Table 20-1 Summary of ASM Commands
Command | Description |
---|---|
cd |
Changes the current directory to the specified directory. |
du |
Displays the total disk space occupied by ASM files in the specified ASM directory and all its subdirectories, recursively. |
exit |
Exits ASMCMD. |
find |
Lists the paths of all occurrences of the specified name (with wildcards) under the specified directory. |
help |
Displays the syntax and description of ASMCMD commands. |
ls |
Lists the contents of an ASM directory, the attributes of the specified file, or the names and attributes of all disk groups. |
lsct |
Lists information about current ASM clients. |
lsdg |
Lists all disk groups and their attributes. |
mkalias |
Creates an alias for a system-generated filename. |
mkdir |
Creates ASM directories. |
pwd |
Displays the path of the current ASM directory. |
rm |
Deletes the specified ASM files or directories. |
rmalias |
Deletes the specified alias, retaining the file that the alias points to. |
Purpose
Changes the current directory to the specified directory.
Syntax and Description
cd dir
dir
may be specified as either an absolute path or a relative path, including the pseudo-directories "." and "..".
Examples
ASMCMD [+DGROUP2/HR] > cd +dgroup1/sample ASMCMD [+DGROUP1/SAMPLE] > cd datafile ASMCMD [+DGROUP1/SAMPLE/DATAFILE] >cd .. ASMCMD [+DGROUP1/SAMPLE] >
Purpose
Displays the total space used for files in the specified directory and in the entire directory tree under it.
Syntax and Description
du [-H] dir
This command is similar to the du -s
command in UNIX. If you do not specify dir
, information about the current directory is displayed. dir
can contain wildcard characters.
The following two values are displayed, both in units of MB.
Used_MB
—This value does not take the mirroring into account. Mirror_used_MB
—This value takes mirroring into account.
For example, if a normal redundancy disk group contains 100 MB of data, then assuming that each file in the disk group is 2-way mirrored, Used_MB
is 100 MB and Mirror_used_MB
is roughly 200 MB.
The -H
flag suppresses column headings from the output.
Example
The following example shows disk space used in the SAMPLE
directory in DGROUP1
, including all directories below SAMPLE
.
ASMCMD [+DGROUP1/SAMPLE] > du Used_MB Mirror_used_MB 1251 2507
Purpose
Displays the absolute paths of all occurrences of the specified name (with wildcards) in a specified directory and its subdirectories.
Syntax and Description
find [-t type] dir name
This command searches the specified directory and all subdirectories below it in the directory tree for the supplied name. name
can be a directory name or a filename, and can include wildcard characters. dir
may also include wildcards. In the output of the command, directory names are suffixed with the slash character (/) to distinguish them from filenames.
You use the -t
flag to find all the files of a particular type (specified as type
). For example, you can search for control files by specifying type
as CONTROLFILE
. Valid values for type
are the following:
CONTROLFILE DATAFILE ONLINELOG ARCHIVELOG TEMPFILE BACKUPSET DATAFILE PARAMETERFILE DATAGUARDCONFIG FLASHBACK CHANGETRACKING DUMPSET AUTOBACKUP XTRANSPORT
Note:
These are the values from thetype
column of the V$ASM_FILE
view.Examples
The following example searches the dgroup1
disk group for files that begin with 'undo':
ASMCMD> find +dgroup1 undo* +dgroup1/SAMPLE/DATAFILE/UNDOTBS1.258.555341963 +dgroup1/SAMPLE/DATAFILE/UNDOTBS1.272.557429239
The following example returns the absolute path of all the control files in the +dgroup1/sample
directory.
ASMCMD> find -t CONTROLFILE +dgroup1/sample * +dgroup1/sample/CONTROLFILE/Current.260.555342185 +dgroup1/sample/CONTROLFILE/Current.261.555342183
Purpose
Displays the syntax of a command and a description of the command parameters.
Syntax and Description
help [command]
If command
is not specified, the help
command displays a list of all the ASMCMD commands and general information about using the ASMCMD utility.
Example
help mkalias
Purpose
Lists the contents of an ASM directory, the attributes of the specified file, or the names and attributes of all disk groups.
Syntax and Description
ls [-lsdrtLaH] [name]
name
can be a filename or directory name, including wildcard characters.
If name
is a directory name, ASMCMD lists the contents of the directory, and, depending on flag settings, information about each directory member. Directories are listed with a trailing slash (/) to distinguish them from files.
If name
is a filename, ASMCMD lists the file, and, depending on flag settings, information about the file. The file must be located in the current directory if the filename is specified with a relative path.
Command flags enable you to modify and customize the output of the command. The following table lists the flags and their descriptions.
Table 20-2 Flags for the ls command
Flag | Description |
---|---|
(none) | Displays only filenames and directory names. |
-l |
Displays extended file information, including striping and redundancy attributes and whether the file was system-generated (indicated by Y under the SYS column) or user-created (as in the case of an alias, indicated by N under the SYS column). When used in the "ls -l + " command, displays extended disk group information. Note that not all possible file attributes or disk group attributes are included. To view the complete set of attributes for a file or a disk group, query the V$ASM_FILE and V$ASM_DISKGROUP views. |
-s |
Displays file space information. |
-d |
If the name argument is a directory, displays information about that directory, rather than the directory contents. Typically used with another flag, such as the -l flag. |
-r |
Reverses the sort order of the listing. |
-t |
Sorts the listing by timestamp (latest first) instead of by name. |
-L |
If the name argument is an alias, displays information on the file that it references. Typically used with another flag, such as the -l flag. |
-a |
For each listed file, displays the absolute path of the alias that references it, if any. |
-H |
Suppresses column headings. |
If you specify all flags, then the command shows a union of their attributes, with duplicates removed. If you enter ls +
, then the command returns information on all disk groups, including whether or not they are mounted.
Examples
ASMCMD [+DGROUP1/SAMPLE/DATAFILE] > ls EXAMPLE.269.555342243 SYSAUX.257.555341961 SYSTEM.256.555341961 UNDOTBS1.258.555341963 UNDOTBS1.272.557429239 USERS.259.555341963 ASMCMD [+DGROUP1/SAMPLE/DATAFILE] > ls -l Type Redund Striped Time Sys Name DATAFILE MIRROR COARSE APR 18 19:16:07 Y EXAMPLE.269.555342243 DATAFILE MIRROR COARSE MAY 09 22:01:28 Y SYSAUX.257.555341961 DATAFILE MIRROR COARSE APR 19 19:16:24 Y SYSTEM.256.555341961 DATAFILE MIRROR COARSE MAY 05 12:28:42 Y UNDOTBS1.258.555341963 DATAFILE MIRROR COARSE MAY 04 17:27:34 Y UNDOTBS1.272.557429239 DATAFILE MIRROR COARSE APR 18 19:16:07 Y USERS.259.555341963 ASMCMD [+DGROUP1/SAMPLE/DATAFILE] > ls -lt Type Redund Striped Time Sys Name DATAFILE MIRROR COARSE MAY 09 22:01:28 Y SYSAUX.257.555341961 DATAFILE MIRROR COARSE MAY 05 12:28:42 Y UNDOTBS1.258.555341963 DATAFILE MIRROR COARSE MAY 04 17:27:34 Y UNDOTBS1.272.557429239 DATAFILE MIRROR COARSE APR 19 19:16:24 Y SYSTEM.256.555341961 DATAFILE MIRROR COARSE APR 18 19:16:07 Y USERS.259.555341963 DATAFILE MIRROR COARSE APR 18 19:16:07 Y EXAMPLE.269.555342243 ASMCMD [+DGROUP1/SAMPLE/DATAFILE] > ls -l undo* Type Redund Striped Time Sys Name DATAFILE MIRROR COARSE MAY 05 12:28:42 Y UNDOTBS1.258.555341963 DATAFILE MIRROR COARSE MAY 04 17:27:34 Y UNDOTBS1.272.557429239 ASMCMD [+DGROUP1/SAMPLE/DATAFILE] > ls -s Block_Size Blocks Bytes Space Name 8192 12801 104865792 214958080 EXAMPLE.269.555342243 8192 48641 398467072 802160640 SYSAUX.257.555341961 8192 61441 503324672 1011875840 SYSTEM.256.555341961 8192 6401 52436992 110100480 UNDOTBS1.258.555341963 8192 12801 104865792 214958080 UNDOTBS1.272.557429239 8192 641 5251072 12582912 USERS.259.555341963 ASMCMD [+DGROUP1] > ls +DGROUP1/SAMPLE CONTROLFILE/ DATAFILE/ ONLINELOG/ PARAMETERFILE/ TEMPFILE/ spfilesample.ora
ASMCMD [+DGROUP1] > ls -l +DGROUP1/SAMPLE Type Redund Striped Time Sys Name Y CONTROLFILE/ Y DATAFILE/ Y ONLINELOG/ Y PARAMETERFILE/ Y TEMPFILE/ N spfilesample.ora=> +DGROUP1/SAMPLE/PARAMETERFILE/spfile.270.555342443
ASMCMD [+DGROUP1] > ls -r +DGROUP1/SAMPLE spfilesample.ora TEMPFILE/ PARAMETERFILE/ ONLINELOG/ DATAFILE/ CONTROLFILE/
ASMCMD [+DGROUP1] > ls -lL example_df2.f Type Redund Striped Time Sys Name DATAFILE MIRROR COARSE APR 27 11:04 N example_df2.f => +DGROUP1/SAMPLE/DATAFILE/EXAMPLE.271.556715087
ASMCMD [+DGROUP1] > ls -a +DGROUP1/SAMPLE/DATAFILE/EXAMPLE.271.556715087 +DGROUP1/example_df2.f => EXAMPLE.271.556715087
ASMCMD [+DGROUP1] > ls -lH +DGROUP1/SAMPLE/PARAMETERFILE PARAMETERFILE MIRROR COARSE MAY 04 21:48 Y spfile.270.555342443 ASMCMD [+DGROUP1] > ls -l + State Type Rebal Unbal Name MOUNTED NORMAL N N DGROUP1/ MOUNTED NORMAL N N DGROUP2/ MOUNTED EXTERN N N DGROUP3/
Purpose
Lists information about current ASM clients. A client is a database that uses disk groups managed by the ASM instance that ASMCMD is currently connected to.
Syntax and Description
lsct [-H] [group]
If group
is specified, information about only that disk group is displayed. The -H
flag suppresses column headings.
Example
This example displays information about the client accessing the dgroup1
disk group.
ASMCMD [+] > lsct dgroup1 DB_Name Status Software_Version Compatible_version Instance_Name sample CONNECTED 10.2.0.0.0 10.2.0.0.0 sample
Purpose
Lists all disk groups and their attributes.
Syntax and Description
lsdg [-H] [group]
Table 20-3 shows the attributes listed for each disk group.
Table 20-3 Attribute descriptions for lsdg command output
Attribute Name | Description |
---|---|
State | Mounted/connected state of the disk group |
Type | Disk group redundancy (NORMAL , HIGH , EXTERNAL ) |
Rebal | Y if a rebalance operation is in progress |
Unbal | Y if the disk group is in need of rebalancing |
Sector | Sector size in bytes |
Block | Block size in bytes |
AU | Allocation Unit size in bytes |
Total_MB | Size of the disk group in MB |
Free_MB | Free space in the disk group in MB, without regard to redundancy. From the V$ASM_DISKGROUP view. |
Req_mir_free_MB | Amount of space that must be available in the disk group to restore full redundancy after the worst failure that can be tolerated by the disk group. This is the REQUIRED_MIRROR_FREE_MB column from the V$ASM_DISKGROUP view. |
Usable_file_MB | Amount of free space, adjusted for mirroring, that is available for new files. From the V$ASM_DISKGROUP view. |
Offline_disks | Number of offline disks in the disk group. Offline disks are eventually dropped. |
Name | Disk group name |
See Oracle Database Administrator's Guide for more information on the attributes that are designated in Table 20-3 as being from the V$ASM_DISKGROUP
view.
If group
is specified, information about only that disk group is listed. The -H
flag suppresses column headings.
Example
The following example lists the attributes of the dgroup2
disk group.
ASMCMD [+] > lsdg dgroup2 State Type Rebal Unbal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Name MOUNTED NORMAL N N 512 4096 1048576 4096 1208 1024 92 0 DGROUP2/
Purpose
Creates an alias for the specified system-generated filename.
Syntax and Description
mkalias file alias
alias
must be in the same disk group as the system-generated file. Only one alias is permitted for each ASM file.
Note:
The SQL*Plus equivalent of themkalias
command is:
ALTER DISKGROUP dg_name ADD ALIAS user_alias FOR file
Example
The following example creates the sysaux.f
alias for the fully qualified filename +DGROUP1/SAMPLE/DATAFILE/SYSAUX.257.555341961
.
ASMCMD [+DGROUP1/SAMPLE/DATAFILE] > mkalias SYSAUX.257.555341961 sysaux.f ASMCMD [+DGROUP1/SAMPLE/DATAFILE] > ls -a none => EXAMPLE.269.555342243 +DGROUP1/SAMPLE/DATAFILE/sysaux.f => SYSAUX.257.555341961 none => SYSTEM.256.555341961 none => UNDOTBS1.258.555341963 none => UNDOTBS1.272.557429239 none => USERS.259.555341963 sysaux.f
Purpose
Creates ASM directories under the current directory.
Syntax and Description
mkdir dir [dir] . . .
The current directory can be a system-created or user-created directory. You cannot create a directory at the root (+) level.
Note:
The SQL*PLUS equivalent of the mkdir command isALTER DISKGROUP
dg_name
ADD DIRECTORY
dir, dir . . .
Example
The following example creates the directories subdir1
and subdir2
at the disk group level in the disk group dgroup1
.
ASMCMD [+DGROUP1] > mkdir subdir1 subdir2 ASMCMD [+DGROUP1] > ls SAMPLE/ example_df2.f subdir1/ subdir2/
Purpose
Displays the absolute path of the current directory.
Syntax and Description
pwd
Example
ASMCMD> pwd +dgroup1/sample/controlfile
Purpose
Deletes the specified ASM files and directories.
Syntax and Description
rm [-rf] name [name] . . .
If name
is a file or alias, rm
can delete it only if it is not currently in use by a client database. If name
is a directory, rm can delete it only if it is empty (unless the -r
flag is used) and it is not a system-generated directory. If name
is an alias, rm
deletes both the alias and the file that the alias references. (To delete just an alias and retain the file that the alias references, use the rmalias
command.)
Note:
The SQL*Plus equivalents of therm
command are:
ALTER DISKGROUP ... DROP FILE ALTER DISKGROUP ... DROP DIRECTORY
If you use a wildcard, rm
deletes all matches except non-empty directories (unless the -r
flag is used).
To recursively delete, use the -r
flag. This enables you to delete a non-empty directory, including all files and directories in it and in the entire directory tree underneath it.
If you use the -r
flag or a wildcard character, rm
prompts you to confirm deletion before proceeding, unless you specify the -f
flag.If a wildcard character matches an alias or a system-generated file that has an alias, both the alias and the system-generated file that it references are deleted. When using the -r
flag, either the system-generated file or the alias needs to be present in the directory in which you run the rm
command.
For example, if you have a user alias, +dg1/dir1/file.alias
that points to +dg/ORCL/DATAFILE/System.256.146589651
, then running the rm -r +dg1/dir1
command will remove +dg1/dir1/file.alias
as well as +dg/ORCL/DATAFILE/System.256.146589651
.
Example
The following example deletes the alias alias293.f
.
ASMCMD [+DGROUP1/SAMPLE/DATAFILE] > rm alias293.f
Purpose
Deletes the specified aliases, retaining the files that the aliases reference.
Syntax and Description
rmalias [-r] alias [alias] . . .
Note:
The SQL*Plus equivalent of thermalias
command is:
ALTER DISKGROUP dg_name DROP ALIAS user_alias
To recursively delete, use the -r
flag. This enables you to delete all aliases in the current directory and in the entire directory tree beneath the current directory. If any user-created directories become empty as a result of deleting aliases, they are deleted also. System-created files and directories are not deleted.
Example
The following example deletes the alias sysaux.f
, retaining the datafile that it references.
ASMCMD [+DGROUP1/SAMPLE/DATAFILE] > rmalias sysaux.f