MOUNT(8) COMMAND REFERENCE MOUNT(8)
NAME
mount, umount - mount and dismount file systems
SYNOPSIS
/etc/mount [ -p ]
/etc/mount -a[fv] [ -t type ]
/etc/mount [ -frv ] [ -t type ] [ -o options ] fsname dir
/etc/mount [ -vf ] [ -o options ] fsname | dir
/etc/umount [ -t type ] [ -h host ]
/etc/umount -a[v]
/etc/umount [ -v ]
DESCRIPTION
The mount command announces to the system that a file system
fsname is to be attached to the file tree at the directory
dir (the directory must already exist because it becomes the
name of the newly-mounted root). The contents of dir are
hidden until the file system is unmounted. If fsname is of
the form host:path the file system type is assumed to be
NFS.
The umount command announces to the system that the file
system fsname previously mounted on directory dir should be
removed; either the file system name or the mounted-on
directory may be used.
Both mount and umount maintain a table of mounted file
systems in /etc/mtab, described in mtab(5). 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(5)) for an entry whose dir or fsname
field matches the given argument. For example, if this line
is in /etc/fstab
/dev/ds00a/usr 4.2 rw 1 1
then the commands mount /usr and mount /dev/ds00a are
shorthand for mount /dev/ds00a /usr.
OPTIONS
mount Options
-p Print the list of mounted file systems in a format
suitable for use in /etc/fstab.
-a Attempt to mount all file systems described in
/etc/fstab. (In this case, fsname and dir are taken
from /etc/fstab.) If a type is specified, all file
systems in /etc/fstab with that type are mounted. File
systems are not necessarily mounted in the order listed
in /etc/fstab.
Printed 4/6/89 1
MOUNT(8) COMMAND REFERENCE MOUNT(8)
-f Fake a new /etc/mtab entry, but do not mount any file
systems.
-v Display a message in verbose mode indicating the file
system being mounted.
-t The next argument is the file system type. The accepted
types are 4.2 and nfs. See fstab(5) for a description
of these file system types.
-r The specified file system is mounted read-only; this is
a shorthand for
mount -o ro fsname dir
Physically write-protected and magnetic tape file
systems must be mounted read-only, or errors occur when
access times are updated, even if an explicit write is
attempted.
-o Specify options, a list of comma-separated words from
the following list; some options are valid for all file
system types, while others apply to a specific type
only.
These options are valid on all file systems (the
default is rw,suid).
rw read/write
ro read-only
suid set-uid execution allowed
nosuid set-uid execution not allowed
noauto do not mount this file system
automatically (mount -a)
These options are specific to 4.2 file systems; the
default is noquota.
quota usage limits enforced
noquota usage limits not enforced
These options are specific to NFS file systems; the
defaults are
fg,retry=1,timeo=7,retrans=3,port=NFS_PORT,hard.
bg if the first mount attempt fails, retry
in the background
Printed 4/6/89 2
MOUNT(8) COMMAND REFERENCE MOUNT(8)
fg retry in foreground
retry=n set number of times to retry mount to n
rsize=n set read buffer size to n bytes;
defaults set by the kernel
wsize=n set write buffer size to n bytes;
defaults set by the kernel
timeo=n set NFS timeout to n tenths of a second
retrans=n set number of NFS retransmissions to n
port=n set server IP port number to n
soft return error if server doesn't respond
hard retry request until server responds
intr allow keyboard interrupts on hard mounts
The bg option causes mount to run in the background if
the server's mountd(8c) does not respond; mount
attempts each request retry=n times before giving up.
Once the file system is mounted, each NFS request made
in the kernel waits timeo=n tenths of a second for a
response. If no response arrives, the timeout is
multiplied by 2 and the request is retransmitted. When
retrans=n retransmissions have been sent with no reply,
a soft mounted file system returns an error on the
request and a hard mounted file system prints a message
and retries the request. File systems that are mounted
rw (read-write) should use the hard option. The intr
option allows keyboard interrupts to kill a process
that is hung waiting for a response on a hard mounted
file system. The number of bytes in a read or write
request can be set with the rsize and wsize options.
umount Options
-h host All file systems listed in /etc/mtab that are
remote-mounted from host are unmounted.
-a Attempt to unmount all file systems currently
mounted (listed in /etc/mtab). In this case, fsname
is taken from /etc/mtab.
-v Display a message in verbose mode indicating the
file system being unmounted.
Printed 4/6/89 3
MOUNT(8) COMMAND REFERENCE MOUNT(8)
EXAMPLES
Mount a local disk:
mount /dev/xy0g /usr
Fake an entry for nd root:
mount -ft 4.2 /dev/nd0 /
Mount all 4.2 file systems:
mount -at 4.2
Mount remote file system:
mount -t nfs serv:/usr/src /usr/src
Mount remote file system:
mount serv:/usr/src /usr/src
Hard mount a remote file system:
mount -o hard serv:/usr/src /usr/src
Save current mount state:
mount -p > /etc/fstab
FILES
/etc/mtab table of mounted file systems
/etc/fstab table of file systems mounted at boot
CAVEATS
You MUST specify -o wsize=2048 when mounting a remote file
system because writes to file systems with files greater
than 8Kb are unreliable.
Mounting file systems full of garbage crashes the system.
No more than one ND client should mount an ND disk partition
as "read-write" or the file system may become corrupted.
If the directory on which a file system is to be mounted is
symbolically linked, the file system is mounted on the
directory to which the symbolic link refers, rather than
being mounted on top of the symbolic link itself.
The permissions of a mounted file system and the mount point
for that file system must be the same. Differences in
permissions can result in Permission denied errors.
Printed 4/6/89 4
MOUNT(8) COMMAND REFERENCE MOUNT(8)
SEE ALSO
mount(2), unmount(2), fstab(5), mountd(8c), nfsd(8).
Printed 4/6/89 5
%%index%%
na:264,99;
sy:363,1478;
de:1841,2195;
op:4036,848;5220,3255;8811,3714;
ex:12861,578;
fi:13439,196;
ca:13635,1264;
se:15235,253;
%%index%%000000000161