Format
MOUNT FILESYSTEM(file_system_name)
MOUNTPOINT(pathname)
TYPE(file_system_type)
MODE(RDWR|READ)
PARM(parameter_string)
TAG(NOTEXT|TEXT,ccsid)
SETUID|NOSETUID
WAIT|NOWAIT
SECURITY|NOSECURITY
SYSNAME (sysname)
AUTOMOVE|AUTOMOVE(indicator,sysname1,sysname2,...,sysnameN)|
NOAUTOMOVE|UNMOUNT
The Indicator is
either INCLUDE or EXCLUDE, which can also be abbreviated as I or E
Description
Use the MOUNT command to logically
mount, or add, a mountable file system to the file system hierarchy.
You can unmount any mounted file system using the UNMOUNT command.
For descriptions of the valid MOUNT parameters for the zFS file system,
see MOUNT in
z/OS Distributed File Service zFS Administration.
For options that are specific to the temporary file system
(TFS), see Mounting the TFS in z/OS UNIX System Services Planning.
Rule: You
must have mount authority before you can issue the MOUNT command.
See the section on mount authority in z/OS UNIX System Services Planning. The TSO MOUNT and UNMOUNT commands performs privileged
operations if the user has read access to the BPX.SUPERUSER resource
in the FACILITY class.
- filesystem(file_system_name)
- Specifies the name of the file system to be added to the file
system hierarchy.
- file_system_name
- For the z/OS® UNIX file
system, this is the fully qualified name of the z/OS UNIX file system data set that contains
the file system. It cannot be a partitioned data set member.
The
file system name that is specified must be unique among previously
mounted file systems. The file system name that is supplied is changed
to all uppercase characters. You can enclose it in single quotation
marks, but they are not required.
If file system('''file_system_name''')
is specified, the file system name is not translated to uppercase.
- MOUNTPOINT(pathname)
- Specifies the path name of the mount point directory, the place
within the file hierarchy where the file system is to be mounted.
This operand is required.
- pathname
- Specifies the path name of the mount point. The path name must
be enclosed in single quotation marks. The name can be a relative
path name or an absolute path name. A relative path name is relative
to the working directory of the TSO/E session (usually the HOME directory).
Therefore, you should usually specify an absolute path name. It can
be up to 1023 characters long. Path names are case-sensitive, so enter
the path name exactly as it is to appear.
Rules: When specifying
the path name, remember the following rules:
- The mount point must be a directory. Any files in that directory
are inaccessible while the file system is mounted.
- Only one file system can be mounted to a mount point at any time.
- TYPE(file_system_type)
- Specifies the type of file system that will perform the logical
mount request. The system converts the TYPE operand value to uppercase
letters. This operand is required.
- file_system_type
- This name must match the TYPE operand of the FILESYSTYPE statement
that activates this physical file system in the BPXPRMxx parmlib member.
The file_system_type value can be up to 8 characters long.
- MODE(RDWR|READ)
- Specifies the type of access the file system is to be opened for.
- RDWR
- Specifies that the file system is to be mounted for read and write
access. RDWR is the default if MODE is omitted.
- READ
- Specifies that the file system is to be mounted for read-only
access.
The z/OS UNIX file
system allows a file system that is mounted using the MODE(READ) option
to be shared as read-only with other systems that share the same DASD.
- PARM('parameter'
- Specifies a parameter string to be passed to the file system type.
The parameter format and content are specified by the file system
type.
Refer to the following documentation for the appropriate
file system-specific options:
- TAG(NOTEXT|TEXT,ccsid)
- Specifies whether the file tags for untagged files in the mounted
file system are implicitly set. File tagging controls the ability
to convert a file's data during file reading and writing. Implicit,
in this case, means that the tag is not permanently stored with the
file. Rather, the tag is associated with the file during reading or
writing, or when stat() type functions are issued. Either TEXT or
NOTEXT, and ccsid must be specified when TAG is specified.
When
the file system is unmounted, the tags are lost.
- NOTEXT
- Specifies that none of the untagged files in the file system are
automatically converted during file reading and writing.
- TEXT
- Specifies that each untagged file is implicitly marked as containing
pure text data that can be converted.
- ccsid
- Identifies the coded character set identifier to be implicitly
set for the untagged file. ccsid is specified
as a decimal value from 0 to 65535. However, when TEXT is specified,
the value must be between 0 and 65535. Other than this, the value
is not checked as being valid and the corresponding code page is not
checked as being installed.
- SETUID|NOSETUID
- Specifies whether the SETUID and SETGID mode bits on executables
in this file system are respected. Also determines whether the APF
extended attribute or the Program Control extended attribute is honored.
- SETUID
- Specifies that the SETUID and SETGID mode bits be respected when
a program in this file system is run. SETUID is the default.
- NOSETUID
- Specifies that the SETUID and SETGID mode bits not be respected
when a program in this file system is run. The program runs as though
the SETUID and SETGID mode bits were not set. Also, if you specify
the NOSETUID option on MOUNT, the APF extended attribute
and the Program Control extended attribute are not honored.
- WAIT|NOWAIT
- Specifies whether to wait for an asynchronous mount to complete
before returning.
- WAIT
- Specifies that MOUNT is to wait for the mount to complete before
returning. WAIT is the default.
- NOWAIT
- Specifies that if the file system cannot be mounted immediately
(for example, a network mount must be done), then the command will
return with a return code indicating that an asynchronous mount is
in progress.
- SECURITY|NOSECURITY
- Specifies whether security checks are to be enforced for files
in this file system. When a z/OS UNIX file
system is mounted with the NOSECURITY option enabled, any new files
or directories that are created are assigned an owner of UID 0, no
matter what UID issued the request.
- SECURITY
- Specifies that normal security checking is done. SECURITY is the
default.
- NOSECURITY
- Specifies that security checking will not be enforced for files
in this file system. A user can access or change any file or directory
in any way.
Security auditing will still be performed if the installation
is auditing successes.
The SETUID, SETGID, APF, and Program
Control attributes may be turned on in files in this file system,
but they are not honored while it is mounted with NOSECURITY.
- SYSNAME (sysname)
- For
systems participating in shared file system, SYSNAME specifies the
particular system on which a mount should be performed. This system
will then become the owner of the file system mounted. This system
must be IPLed with SYSPLEX(YES).
IBM® recommends that you omit the
SYSNAME parameter or specify SYSNAME(system_name)
where system_name is the name of this system.
- sysname
- sysname is a 1–8 alphanumeric name of a system participating in
shared file system.
- AUTOMOVE(indicator,sysname1,...,sysnameN)|NOAUTOMOVE|UNMOUNT
- These
parameters apply only in a sysplex where systems are exploiting the
shared file system capability. They specify what is to happens to
the ownership of a file system when a shutdown, PFS termination, dead
system takeover, or file system move occurs. The default setting is
AUTOMOVE where the file system will be randomly moved to another system
(no system list used).
Indicator is
either INCLUDE or EXCLUDE, which can also be abbreviated as I or E
- AUTOMOVE
- AUTOMOVE indicates that ownership of the file system can be automatically
moved to another system participating in a shared file system. AUTOMOVE
is the default.
- AUTOMOVE(INCLUDE,sysname1,sysname2,...,sysnameN) or AUTOMOVE(I,sysname1,sysname2,...,sysnameN)
- The INCLUDE indicator with a system list provides an ordered list
of systems to which the file system's ownership could be moved. sysnameN may
be a system name, or an asterisk (*). The asterisk acts as a wildcard
to allow ownership to move to any other participating system and is
only permitted in place of a system name as the last entry of a system
list.
- AUTOMOVE(EXCLUDE,sysname1,sysname2,...,sysnameN) or AUTOMOVE(E,sysname1,sysname2,...,sysnameN)
- The EXCLUDE indicator with a system list provides a list of systems
to which the file system's ownership should not be moved.
- NOAUTOMOVE
- NOAUTOMOVE prevents movement of the file system's ownership in
some situations.
- UNMOUNT
- UNMOUNT allows the file system to be unmounted in some situations.
Guidelines: Follow
these guidelines when unmounting the file system:
- Define your version and sysplex root file systems as AUTOMOVE,
and define your system-specific file systems as UNMOUNT.
- Do not define a file system as NOAUTOMOVE or UNMOUNT and
a file system underneath is as AUTOMOVE;
in this case, the file system defined as AUTOMOVE will
not be recovered after a system failure until the failing system is
restarted.
See z/OS UNIX System Services Planning for
more information about shared file systems.
Usage notes
- The /samples directory contains sample MOUNT
commands (called mountx).
- When the mount is done asynchronously (NOWAIT was specified and
return code 4 was returned), you can determine if the mount has completed
with one of the following:
- The df shell command
- The DISPLAY OMVS,F operator command (see z/OS MVS System Commands)
- The MOUNT table option on the File Systems pull-down in the ISPF
Shell (accessed by the ISHELL command)
- In order to mount a file system as the system root file system,
the caller must be a superuser. Also, a file system can only be mounted
as the system root file system if the root file system was previously
unmounted.
- If you have previously unmounted the root file system, a dummy
file system or SYSROOT is displayed as the current root file system.
During the time when SYSROOT is displayed as the root, any operation
that requires a valid file system will fail. When you subsequently
mount a new root file system on mount point /, that new file
system will replace SYSROOT. When a new root file system has been
mounted, you should terminate any current dubbed users or issue a chdir command,
using a full path name to the appropriate directory. This way, the
users can access the new root file system. Otherwise, an error will
occur when a request is made requiring a valid file system.
- Systems exploiting shared file system will have I/O to an OMVS
couple data set. Because of these I/O operations to the CDS, each
mount request requires additional system overhead. You will need to
consider the effect that this will have on your recovery time if a
large number of mounts are required on any system participating in
shared file system.
- The TAG parameter is intended for file systems that don't support
storing the file tag, such as NFS remote file systems.
- Do not use the TAG parameter simultaneously with the NFS Client
Xlate option. If you do, the mount will fail.
- The UNMOUNT keyword is not available to automounted file systems.
File system recovery and TSO MOUNT
File
system recovery in a shared file system environment takes into consideration
file system specifications such as AUTOMOVE | NOAUTOMOVE | UNMOUNT,
and whether or not the file system is mounted read-only or read/write.
Generally,
when an owning system fails, ownership over its AUTOMOVE mounted file
systems is moved to another system and the file is usable. However,
if a file system is mounted read/write and the owning system fails,
then all file system operations for files in that file system will
fail. This is because data integrity is lost when the file system
owner fails. All files should be closed (BPX1CLO) and reopened (BPX1OPN)
when the file system is recovered. (The BPX1CLO and BPX1OPN callable
services are discussed in z/OS UNIX System Services Programming: Assembler Callable Services Reference.).
For
file systems that are mounted read-only, specific I/O operations that
were in progress at the time the file system owner failed may need
to be re-attempted. Otherwise, the file system is usable.
In
some situations, even though a file system is mounted AUTOMOVE, ownership
of the file system may not be immediately moved to another system.
This may occur, for example, when a physical I/O path from another
system to the volume where the file system resides is not available.
As a result, the file system becomes unowned (the system will issue
message BPXF213E when this occurs). This is true if the file system
is mounted either read/write or read-only. The file system still exists
in the file system hierarchy so that any dependent file systems that
are owned by another system are still usable.
However, all
file operations for the unowned file system will fail until a new
owner is established. The shared file system support will continue
to attempt recovery of AUTOMOVE file systems on all systems in the
sysplex that are enabled for shared file system. Should a subsequent
recovery attempt succeed, the file system transitions from the unowned
to the active state.
Applications using files in unowned file
systems must close (BPX1CLO) those files and reopen (BPX1OPN) them
after the file system is recovered.
File systems that are mounted
NOAUTOMOVE will become unowned when the file system owner exits the
sysplex. The file system will remain unowned until the original owning
system restarts or until the unowned file system is unmounted. Since
the file system still exists in the file system hierarchy, the file
system mount point is still in use.
An unowned file system
is a mounted file system that does not have an owner. The file system
still exists in the file system hierarchy. As such, you can recover
or unmount an unowned file system.
File systems associated
with a 'never move' PFS will be unmounted during dead system recovery.
For example, TFS is a 'never move' PFS and will be unmounted, as well
as any file systems mounted on it, when the owning system leaves the
sysplex.
As stated in Usage notes,
the UNMOUNT keyword is not available to automounted file systems.
However, during dead system recovery processing for an automounted
file system (whose owner is the dead system), the file system is unmounted
if it is not being referenced by any other system in the sysplex.
Return codes
- 0
- Processing successful.
- 4
- Processing incomplete. An asynchronous mount is in progress.
- 12
- Processing unsuccessful. An error message has been issued.
Examples
- To mount HFS.WORKDS on the directory /u/openuser,
enter:
MOUNT filesystem('HFS.WORKDS') MOUNTPOINT('/u/openuser') TYPE(HFS)
- The following example mounts the z/OS UNIX directory /u/shared_data,
which resides on the remote host named mvshost1, onto the local
directory /u/jones/mnt. The command may return
before the mount is complete, allowing the mount to be processed in
parallel with other work. The SETUID and SETGID bits are honored on
any executable programs:
MOUNT filesystem('MVSHOST1.SHARE.DATA') MOUNTPOINT('/u/jones/mnt')
TYPE(NFSC) PARM('mvshost1:/hfs/u/shared_data') NOWAIT SETUID
- Examples for using the TAG parameter are:
TAG(TEXT,819) identifies text files containing ASCII
(ISO-8859-1) data.
TAG(TEXT,1047) identifies text files containing EBCDIC
(ISO-1047) data.
TAG(NOTEXT,65535) tags files as containing binary or unknown
data.
TAG(NOTEXT,0) is the equivalent of not specifying the TAG
parameter at all.
TAG(NOTEXT,273) tags files with the German code set (ISO-273),
but is ineligible for automatic conversion.