789e4d2f20
- Use appropriate macros for command arguments. - Increase option list indentation for better readability. MFC after: 3 days
191 lines
5.1 KiB
Groff
191 lines
5.1 KiB
Groff
.\" Copyright (c) 1980, 1989, 1991, 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" @(#)umount.8 8.2 (Berkeley) 5/8/95
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd April 14, 2020
|
|
.Dt UMOUNT 8
|
|
.Os
|
|
.Sh NAME
|
|
.Nm umount
|
|
.Nd unmount file systems
|
|
.Sh SYNOPSIS
|
|
.Nm
|
|
.Op Fl fNnv
|
|
.Ar special ... | node ... | fsid ...
|
|
.Nm
|
|
.Fl a | A
|
|
.Op Fl F Ar fstab
|
|
.Op Fl fnv
|
|
.Op Fl h Ar host
|
|
.Op Fl t Ar type
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
utility calls the
|
|
.Xr unmount 2
|
|
system call to remove a file system from the file system tree.
|
|
The file system can be specified by its
|
|
.Ar special
|
|
device or remote node
|
|
.Pq Ar rhost Ns Cm \& : Ns Ar path ,
|
|
the path to the mount point
|
|
.Ar node
|
|
or by the file system ID
|
|
.Ar fsid
|
|
as reported by
|
|
.Dq mount -v
|
|
when run by root.
|
|
.Pp
|
|
The options are as follows:
|
|
.Bl -tag -width "-F fstab"
|
|
.It Fl a
|
|
All the file systems described in
|
|
.Xr fstab 5
|
|
are unmounted.
|
|
.It Fl A
|
|
All the currently mounted file systems except
|
|
the root are unmounted.
|
|
.It Fl F Ar fstab
|
|
Specify the
|
|
.Pa fstab
|
|
file to use.
|
|
.It Fl f
|
|
The file system is forcibly unmounted.
|
|
Active special devices continue to work,
|
|
but all other files return errors if further accesses are attempted.
|
|
The root file system cannot be forcibly unmounted.
|
|
For NFS, a forced dismount can take up to 1 minute or more to
|
|
complete against an unresponsive server and may throw away
|
|
data not yet written to the server for this case.
|
|
If a process, such as
|
|
.Nm
|
|
without the
|
|
.Fl f
|
|
flag is hung on an
|
|
.Tn NFS
|
|
mount point, use the
|
|
.Fl N
|
|
flag instead.
|
|
Also, doing a forced dismount of an NFSv3 mount when
|
|
.Xr rpc.lockd 8
|
|
is running is unsafe and can result in a crash.
|
|
.It Fl h Ar host
|
|
Only file systems mounted from the specified host will be
|
|
unmounted.
|
|
This option implies the
|
|
.Fl A
|
|
option and, unless otherwise specified with the
|
|
.Fl t
|
|
option, will only unmount
|
|
.Tn NFS
|
|
file systems.
|
|
.It Fl N
|
|
Do a forced dismount of an
|
|
.Tn NFS
|
|
mount point without checking the mount path.
|
|
This option can only be used with the path to the mount point
|
|
.Ar node
|
|
and the path must be specified exactly as it was at mount time.
|
|
This option is useful when a process is hung waiting for an unresponsive
|
|
.Tn NFS
|
|
server while holding a vnode lock on the mounted-on vnode, such that
|
|
.Nm
|
|
with the
|
|
.Fl f
|
|
flag can't complete.
|
|
Using this option can result in a loss of file updates that have not been
|
|
flushed to the
|
|
.Tn NFS
|
|
server.
|
|
.It Fl n
|
|
Unless the
|
|
.Fl f
|
|
is used, the
|
|
.Nm
|
|
will not unmount an active file system.
|
|
It will, however, perform a flush.
|
|
This flag disables this behaviour, preventing the flush
|
|
if there are any files open.
|
|
.It Fl t Ar type
|
|
Is used to indicate the actions should only be taken on
|
|
file systems of the specified type.
|
|
More than one type may be specified in a comma separated list.
|
|
The list of file system types can be prefixed with
|
|
.Dq no
|
|
to specify the file system types for which action should
|
|
.Em not
|
|
be taken.
|
|
For example, the
|
|
.Nm
|
|
command:
|
|
.Bd -literal -offset indent
|
|
umount -a -t nfs,nullfs
|
|
.Ed
|
|
.Pp
|
|
unmounts all file systems of the type
|
|
.Tn NFS
|
|
and
|
|
.Tn NULLFS
|
|
that are listed in the
|
|
.Xr fstab 5
|
|
file.
|
|
.It Fl v
|
|
Verbose, additional information is printed out as each file system
|
|
is unmounted.
|
|
.El
|
|
.Sh ENVIRONMENT
|
|
.Bl -tag -width ".Ev PATH_FSTAB"
|
|
.It Ev PATH_FSTAB
|
|
If the environment variable
|
|
.Ev PATH_FSTAB
|
|
is set, all operations are performed against the specified file.
|
|
.Ev PATH_FSTAB
|
|
will not be honored if the process environment or memory address space is
|
|
considered
|
|
.Dq tainted .
|
|
(See
|
|
.Xr issetugid 2
|
|
for more information.)
|
|
.El
|
|
.Sh FILES
|
|
.Bl -tag -width /etc/fstab -compact
|
|
.It Pa /etc/fstab
|
|
file system table
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr unmount 2 ,
|
|
.Xr fstab 5 ,
|
|
.Xr autounmountd 8 ,
|
|
.Xr mount 8
|
|
.Sh HISTORY
|
|
A
|
|
.Nm
|
|
utility appeared in
|
|
.At v1 .
|