mount(1M) mount(1M)
NAME
mount, umount - mount and unmount filesystems
SYNOPSIS
mount
mount [ -M altmtab ] [ -P prefix ] -p
mount [ -h host ] [ -fnrv ]
mount -a[cfnvC] [ -t type ] [ -T list ] [-m numprocs ]
mount [ -cfnvC ] [ -t type ] [ -T list ] [ -b list ]
mount [ -cfnrvC ] [ -t type ] [ -T list ] [ -o options ] fsname dir
mount [ -cfnrvC ] [ -o options ] fsname | dir
umount -a[kv] [ -t type ] [-m numprocs ] [ -T list ]
umount -h host [ -kv ] [-m numprocs ] [ -b list ]
umount [ -kv ] fsname | dir [ fsname | dir ] ...
DESCRIPTION
mount attaches a named filesystem fsname to the filesystem hierarchy at
the pathname location dir. The directory dir must already exist. It
becomes the name of the newly mounted root. The contents of dir are
hidden until the filesystem is unmounted. If fsname is of the form
host:path, the filesystem type is assumed to be nfs.
umount unmounts a currently mounted filesystem, which can be specified
either as a mounted-on directory or a filesystem.
mount and umount maintain a table of mounted filesystems in /etc/mtab,
described in mtab(4). If invoked without an argument, mount displays the
table. If invoked with only one of fsname or dir, mount searches the
file /etc/fstab (see fstab(4)) for an entry whose dir or fsname field
matches the given argument. For example, if this line is in /etc/fstab:
/dev/usr /usr xfs rw 0 0
then the commands mount /usr and mount /dev/usr are shorthand for
mount /dev/usr /usr.
MOUNT OPTIONS
-a Attempt to mount all the filesystems described in /etc/fstab.
(In this case, fsname and dir are taken from /etc/fstab.) If a
type is specified with -t, all of the filesystems in /etc/fstab
with that type are mounted. Multiple types may be specified
with the -T option. Filesystems are not necessarily mounted in
the order listed in /etc/fstab. If the -m option is specified,
its argument is used to limit the number of processes used to
mount all of the file systems in parallel.
-b list (all-but) Attempt to mount all of the filesystems listed in
/etc/fstab except for those associated with the directories
contained in list. list consists of one or more directory
names separated by commas.
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-c Invoke fsstat(1M) on each filesystem being mounted, and if it
indicates that the filesystem is dirty, call fsck(1M) to clean
the filesystem. fsck is passed the -y option. This option
applies only to EFS filesystems, not to XFS filesystems.
-f Fake a new /etc/mtab entry, but do not actually mount any
filesystems.
-h host Mount all filesystems listed in /etc/fstab that are remote-
mounted from host.
-m numprocs
Use no more than numprocs processes to mount the specified file
systems in parallel. The default number of processes used is
16. This option is only meaningful when used in conjunction
with the -a option.
-n Mount the filesystem without making an entry in /etc/mtab.
-o options
Specify options, a list of comma-separated words, described in
fstab(4).
-p Print the list of mounted filesystems in a format suitable for
use in /etc/fstab.
-r Mount the specified filesystem read-only. This is a shorthand
for:
mount -o ro fsname dir
Physically write-protected and magnetic tape filesystems must
be mounted read-only, or errors occur when access times are
updated, whether or not any explicit write is attempted.
-t type The next argument is the filesystem type. The accepted types
are proc, efs, xfs, nfs, fd, cachefs, dos, hfs and iso9660; see
fstab(4) and the filesystems(4) man page for more information
on the supported filesystem types. for a description of these
filesystem types. When this option is used, mount calls
another program of the form mount_typename, where typename is
one of the above types. This program must be on the default
path.
-T list The next argument is a comma-separated list of filesystem
types. This option is usually used in combination with -a or
-b.
-v (verbose) mount displays a message indicating the filesystem
being mounted and any problems encountered.
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-M altmtab
Instead of /etc/mtab, use the mtab or fstab altmtab.
-P prefix Used with the -p option, prepends prefix to the emitted
filesystem and directory paths. Doesn't alter pathnames
embedded in the options, such as the filesystem's raw=path raw
device pathname.
UMOUNT OPTIONS
-a Attempt to unmount all the filesystems currently mounted
(listed in /etc/mtab). In this case, fsname is taken from
/etc/mtab.
NOTE: The use of umount -a is NOT symmetric with mount -a,
because the first is based on the mtab file, while the second
is based on the fstab file. Typical differences are the /proc,
/hw, and /dev/fd filesystems.
-b list (all-but) Attempt to unmount all of the filesystems currently
mounted except for those associated with the directories
contained in list. list consists of one or more directory
names separated by commas. Using
umount -a
itself is not usually a good idea, because it can not be
reversed by the command
mount -a
since a number of filesystems are often not in the /etc/fstab
file. Among these are the proc and fd filesystems. Instead,
use a command similar to
umount -T xfs,efs
-h host Unmount all filesystems listed in /etc/mtab that are remote-
mounted from host.
-m numprocs
Use no more than numprocs processes to unmount the specified
file systems in parallel. The default number of processes used
is 16. This option is only meaningful when used in conjunction
with the -a, -t or -h options.
-k Attempt to kill processes that have open files or current
directories in the appropriate filesystems and then unmount
them.
-t type Unmount all filesystems of a given filesystem type. The
accepted types are proc, efs, xfs, nfs, fd, cachefs, dos, hfs,
and iso9660.
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-T list Unmount all filesystems whose type is in the comma-separated
list given.
-v (verbose) umount displays a message indicating the filesystem
being unmounted and any problems encountered.
-C Disable overlapping partition/volume checks.
By default mount checks to see if the destination partition or
logical volume overlaps any mounted or reserved partitions in
the system. If an overlap or mount conflict is found, the user
will be notified and prevented from potentially corrupting the
existing data. For systems with a large number of disks, this
additional checking may add noticable overhead to the command's
execution time. For situations where command performance is
necessary, this switch may be used to disable the safeguards.
Due to the potential for user-error causing corrupted
filesystems or other on-disk data corruption, we strongly
discourage use of this switch in normal operation.
EXAMPLES
mount /dev/usr /usr mount a local disk
mount -avt xfs mount all xfs filesystems; be verbose
mount -t nfs server:/d /net/d mount remote filesystem
mount server:/d /net/d same as above
mount -o soft server:/d /net/d same as above but soft mount
mount -p > /etc/fstab save current mount state
mount -t dos /dev/rdsk/fds0d2.3.5 /floppy
mount a MS-DOS floppy
mount -t hfs /dev/rdsk/fds0d3.3.5hi /floppy
mount a Macintosh HFS floppy
mount -t hfs /dev/rdsk/dks0d7vol /cdrom
mount an HFS CD-ROM
mount -t iso9660 /dev/rdsk/dks0d7vol /cdrom
mount an ISO 9660 CD-ROM
mount server:/cdrom /net/cdrom mount remote iso9660 filesystem
mount -M /root/etc/fstab -P /root -p |
sed 's;raw=/;raw=/root/' >> /etc/fstab
append /root/etc/fstab with /root
prefix to currently active fstab.
umount -t nfs -b /foo unmount all nfs filesystems except /foo
ERROR MESSAGES
From mount:
mount: device on mountdir: Invalid argument
This message appears for a wide variety of problems. It doesn't
usually indicate that you have specified the command line
incorrectly; rather that there is something wrong with the disk
partition, the filesystem in the disk partition, or the mount
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directory. For example, this error message occurs if you try to
mount a device that doesn't contain a valid filesystem.
From umount:
mountdir: Resource busy
Possible causes of a this message are: open files in the filesystem,
programs being executed from the filesystems, and users whose
current directory is in the filesystem.
Usually it is not possible to unmount the /usr filesystem because
many daemons, such as /usr/lib/lpsched, /usr/etc/ypbind, and
/usr/etc/syslogd, execute from the /usr filesystem. The simplest
way to make sure the /usr filesystem is not busy is to bring the
system down to single-user mode with the single(1M) command.
You can force all filesystems except the root filesystem to be
unmounted with the umount -k option (note that this kills
processes). To unmount the root filesystem, you must be running the
miniroot.
FILES
/etc/fstab filesystem table
/etc/mtab mount table
/etc/mntproc script to mount /proc
SEE ALSO
fsck(1M), mountd(1M), nfsd(1M), mount(2), umount(2), filesystems(4),
fstab(4), mtab(4).
BUGS
umount can mismanage the /etc/mtab mount table if another mount or umount
call is in progress at the same time.
Mount calls another "helper" program of the form mounttypename, where
typename is one of the accepted mount types. If this program is not on
the default path, then mount returns with an error message about unknown
filesystem. The user must make sure that the helper mount program is in
the path. For example, /usr/etc must be in the path to mount an iso9660
CD.
NOTE
If the directory on which a filesystem is to be mounted is a symbolic
link, the filesystem is mounted on the directory to which the symbolic
link refers, rather than being mounted on top of the symbolic link
itself.
The helper program mountiso9660 is in the optional package eoe.sw.cdrom.
This package must be installed in order to mount iso9660 filesystems.
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The mount command attempts to assure that the blocksize of the device
matches that specified in the device volume header.
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