chmount - Change the mount attributes of a file system

Format

chmount [-DRrsw] [-dsysname] [-d destsys] [-a yes|no|unmount|include,|exclude,sysname1,...,sysnameN] pathname ...

Description

The chmount shell command, which is located in /usr/sbin, changes the mount attributes of a specified file system.

Restriction: A chmount user must have UID(0) or at least have READ access to the SUPERUSER.FILESYS.MOUNT resource found in the UNIXPRIV class.

Options

-a yes |no | unmount|include,sysname1,...,sysnameN|exclude,sysname1,...,sysnameN
The -a option specifies the AUTOMOVE attribute of the file system in a sysplex environment where systems are exploiting the shared file system capability.
  • -a yes allows the system to automatically move logical ownership for a specified file system as needed. This is the default.
  • -a no prevents ownership movement in some situations.
  • -a unmount unmounts the file system in some situations.
  • -a include,sysname1,...,sysnameN specifies a list of systems, in priority order, to which the file system's ownership can be moved. include can be abbreviated to i.
  • -a exclude,sysname1,...,sysnameN specifies a list of systems, in priority order, to which the file system's ownership cannot be moved. exclude can be abbreviated to e.
For information about the behavior of the AUTOMOVE options, see Managing the movement of data in z/OS UNIX System Services Planning.
-D
Reassigns logical ownership of a file system to any available file system that is participating in shared file system.
-d destsys
To designate a specific reassignment, use -d destsys, where destsys becomes the logical owner of a file system in a shared file system environment.
-R
Changes the attributes of a specified file system and all file systems that are mounted under it in the file system hierarchy.
-r
Switches the specified file system to read-only mode.
-s
Remounts the specified file system but does not change the current mode.
-w
Switches the specified file system to read/write mode.

pathname... specifies the path names to use for locating the file systems that need attributes that are changed.

Examples

To move ownership of the file system that contains /u/wjs to SY1: 
chmount -d SY1 /u/wjs

Usage notes

Because the path name for chmount and unmount is a node, symbolic links cannot be followed unless a trailing slash is added to the symbolic link name. For example, if /etc has been converted into a symbolic link, /etc -> $SYSNAME/etc, issuing chmount -w /etc without the trailing slash will result in trying to chmount -w /etc -> $SYSNAME/etc. Depending on the security access for the symbolic link, RACF® errors might occur. However, if you specify chmount -w /etc/ with the trailing slash, the symbolic link will be followed and RACF will determine the access from the file being linked to.

Exit values

0
Successful completion

Related information

mount, unmount