.\" $OpenBSD: mount.8,v 1.5 1997/03/10 04:27:41 millert Exp $ .\" $NetBSD: mount.8,v 1.11 1995/07/12 06:23:21 cgd Exp $ .\" .\" 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. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. 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. .\" .\" @(#)mount.8 8.7 (Berkeley) 3/27/94 .\" .Dd March 27, 1994 .Dt MOUNT 8 .Os BSD 4 .Sh NAME .Nm mount .Nd mount file systems .Sh SYNOPSIS .Nm mount .Op Fl Aadfruvw .Op Fl t Ar type .Nm mount .Op Fl dfruvw .Ar special | node .Nm mount .Op Fl dfruvw .Op Fl o Ar options .Op Fl t Ar type .Ar special node .Sh DESCRIPTION The .Nm mount command invokes a filesystem-specific program to prepare and graft the .Ar special device or remote node (rhost:path) on to the file system tree at the point .Ar node . If either .Ar special or .Ar node are not provided, the appropriate information is taken from the .Xr fstab 5 file. .Pp The system maintains a list of currently mounted file systems. If no arguments are given to .Nm mount, this list is printed. .Pp The options are as follows: .Bl -tag -width indent .It Fl A Causes .Nm mount to try to mount all of the file systems listed in the .Xr fstab table except those for which the .Dq noauto option is specified. .It Fl a Similar to the .Fl A flag, except that if a file system (other than the root file system) appears to be already mounted, .Nm mount will not try to mount it again. .Nm Mount assumes that a file system is already mounted if a file system with the same type is mounted on the given mount point. More stringent checks are not possible because some file system types report strange values for the mounted-from device for mounted file systems. .It Fl d Causes everything to be done except for the invocation of the filesystem-specific program. This option is useful in conjunction with the .Fl v flag to determine what the .Nm mount command is trying to do. .It Fl f Forces the revocation of write access when trying to downgrade a filesystem mount status from read-write to read-only. .It Fl o Options are specified with a .Fl o flag followed by a comma separated string of options. The following options are available: .Bl -tag -width indent .It async All .Tn I/O to the file system should be done asynchronously. This is a .Em dangerous flag to set, and should not be used unless you are prepared to recreate the file system should your system crash. .It force The same as .Fl f ; forces the revocation of write access when trying to downgrade a filesystem mount status from read-write to read-only. .It noatime Do not update atime on files in the system unless the mtime or ctime is being changed as well. This option is useful for laptops and news servers where one does not want the extra disk activity associated with updating the atime. .It noaccesstime Synonym for noatime provided for compatibility with other OS's. .It nodev Do not interpret character or block special devices on the file system. This option is useful for a server that has file systems containing special devices for architectures other than its own. .It noexec Do not allow execution of any binaries on the mounted file system. This option is useful for a server that has file systems containing binaries for architectures other than its own. .It nosuid Do not allow set-user-identifier or set-group-identifier bits to take effect. .It rdonly The same as .Fl r ; mount the file system read-only (even the super-user may not write it). .It sync All .Tn I/O to the file system should be done synchronously. .It update The same as .Fl u ; indicate that the status of an already mounted file system should be changed. .It union Causes the namespace at the mount point to appear as the union of the mounted filesystem root and the existing directory. Lookups will be done in the mounted filesystem first. If those operations fail due to a non-existent file the underlying directory is then accessed. All creates are done in the mounted filesystem. .El .Pp Any additional options specific to a given filesystem type (see the .Fl t option) may be passed as a comma separated list; these options are distinguished by a leading .Dq \&- (dash). Options that take a value are specified using the syntax -option=value. For example, the mount command: .Bd -literal -offset indent mount -t mfs -o nosuid,-N,-s=4000 /dev/dk0b /tmp .Ed .Pp causes .Nm mount to execute the equivalent of: .Bd -literal -offset indent /sbin/mount_mfs -o nosuid -N -s 4000 /dev/dk0b /tmp .Ed .It Fl r The file system is to be mounted read-only. Mount the file system read-only (even the super-user may not write it). The same as the .Dq rdonly argument to the .Fl o option. .It Fl t Ar type The argument following the .Fl t is used to indicate the file system type. The type .Ar ffs is the default. The \fI-t\fP option can be used to indicate that the actions should only be taken on filesystems of the specified type. More than one type may be specified in a comma separated list. The list of filesystem types can be prefixed with .Dq no to specify the filesystem types for which action should .Em not be taken. For example, the .Nm mount command: .Bd -literal -offset indent mount -a -t nonfs,mfs .Ed .Pp mounts all filesystems except those of type .Tn NFS and .Tn MFS . .Pp .Nm Mount will attempt to execute a program in .Pa /sbin/mount_ Ns Em XXX where .Em XXX is replaced by the type name. For example, nfs filesystems are mounted by the program .Pa /sbin/mount_nfs . .It Fl u The .Fl u flag indicates that the status of an already mounted file system should be changed. Any of the options discussed above (the .Fl o option) may be changed; also a file system can be changed from read-only to read-write or vice versa. An attempt to change from read-write to read-only will fail if any files on the filesystem are currently open for writing unless the .Fl f flag is also specified. The set of options is determined by first extracting the options for the file system from the .Xr fstab table, then applying any options specified by the .Fl o argument, and finally applying the .Fl r or .Fl w option. .It Fl v Verbose mode. .It Fl w The file system object is to be read and write. .El .Pp The options specific to the various file system types are described in the manual pages for those file systems' .Nm mount_XXX commands. For instance the options specific to Berkekely Fast File Systems are described in the .Xr mount_ffs 8 manual page. .Sh FILES .Bl -tag -width /etc/fstab -compact .It Pa /etc/fstab file system table .El .Sh SEE ALSO .Xr mount 2 , .Xr fstab 5 , .Xr mount_ados 8 , .Xr mount_cd9660 8 , .Xr mount_fdesc 8 , .Xr mount_ffs 8 , .Xr mount_kernfs 8 , .Xr mount_lfs 8 , .Xr mount_mfs 8 , .Xr mount_msdos 8 , .Xr mount_nfs 8 , .Xr mount_null 8 , .Xr mount_portal 8 , .Xr mount_procfs 8 , .Xr mount_umap 8 , .Xr mount_union 8 , .Xr umount 8 .Sh HISTORY A .Nm mount command appeared in .At v6 .