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mmlinkfileset Command
Name
mmlinkfileset – Creates a junction that references the root directory of a GPFS fileset.
Synopsis
mmlinkfileset Device FilesetName [-J JunctionPath]
Description
The mmlinkfileset command creates a junction at JunctionPath that references the root directory of
FilesetName. The junction is a special directory entry, much like a POSIX hard link, that connects a name
in a directory of one fileset, the parent, to the root directory of a child fileset. From the user’s viewpoint, a
junction always appears as if it were a directory, but the user is not allowed to issue the unlink or rmdir
commands on a junction. Instead, the mmunlinkfileset command must be used to remove a junction.
If JunctionPath is not specified, the junction is created in the current directory with the name FilesetName.
The user may use the mv command on the directory to move to a new location in the parent fileset, but
the mv command is not allowed to move the junction to a different fileset.
For information on GPFS filesets, see the chapter Policy-based data management for GPFS in General
Parallel File System: Advanced Administration Guide.
Parameters
Device The device name of the file system that contains the fileset.
File system names need not be fully-qualified. fs0 is as acceptable as
/dev/fs0.
FilesetName Specifies the name of the fileset to be linked. It must not already be linked
into the namespace.
-J JunctionPath Specifies the name of the junction. The name must not refer to an existing
file system object.
Exit status
0 Successful completion.
nonzero A failure has occurred.
Security
You must have root authority to run the mmlinkfileset command.
You may issue the mmlinkfileset command from any node in the GPFS cluster.
When using the rcp and rsh commands for remote communication, a properly configured .rhosts file must
exist in the root user’s home directory on each node in the GPFS cluster. If you have designated the use
of a different remote communication program on either the mmcrcluster or the mmchcluster command,
you must ensure:
1. Proper authorization is granted to all nodes in the GPFS cluster.
2. The nodes in the GPFS cluster can communicate without the use of a password, and without any
extraneous messages.
194 GPFS: Administration and Programming Reference