e3fbf603a0
the number of days between backups. All it says is frequency, with no units given. It likely should say "the interval in days between backups" instead, but not today.
324 lines
9.1 KiB
Groff
324 lines
9.1 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. 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.
|
|
.\"
|
|
.\" @(#)fstab.5 8.1 (Berkeley) 6/5/93
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd November 23, 2008
|
|
.Dt FSTAB 5
|
|
.Os
|
|
.Sh NAME
|
|
.Nm fstab
|
|
.Nd static information about the file systems
|
|
.Sh SYNOPSIS
|
|
.In fstab.h
|
|
.Sh DESCRIPTION
|
|
The file
|
|
.Nm
|
|
contains descriptive information about the various file
|
|
systems.
|
|
.Nm
|
|
is only read by programs, and not written;
|
|
it is the duty of the system administrator to properly create
|
|
and maintain this file.
|
|
Each file system is described on a separate line;
|
|
fields on each line are separated by tabs or spaces.
|
|
The order of records in
|
|
.Nm
|
|
is important because
|
|
.Xr fsck 8 ,
|
|
.Xr mount 8 ,
|
|
and
|
|
.Xr umount 8
|
|
sequentially iterate through
|
|
.Nm
|
|
doing their thing.
|
|
.Pp
|
|
The first field,
|
|
.Pq Fa fs_spec ,
|
|
describes the special device or
|
|
remote file system to be mounted.
|
|
.Pp
|
|
The second field,
|
|
.Pq Fa fs_file ,
|
|
describes the mount point for the file system.
|
|
For swap partitions, this field should be specified as ``none''.
|
|
.Pp
|
|
The third field,
|
|
.Pq Fa fs_vfstype ,
|
|
describes the type of the file system.
|
|
The system can support various file system types.
|
|
Only the root, /usr, and /tmp file systems need be statically
|
|
compiled into the kernel;
|
|
everything else will be automatically loaded at mount
|
|
time.
|
|
(Exception: the FFS cannot currently be demand-loaded.)
|
|
Some people still prefer to statically
|
|
compile other file systems as well.
|
|
.Pp
|
|
The fourth field,
|
|
.Pq Fa fs_mntops ,
|
|
describes the mount options associated with the file system.
|
|
It is formatted as a comma separated list of options.
|
|
It contains at least the type of mount (see
|
|
.Fa fs_type
|
|
below) plus any additional options appropriate to the file system type.
|
|
See the options flag
|
|
.Pq Fl o
|
|
in the
|
|
.Xr mount 8
|
|
page and the file system specific page, such as
|
|
.Xr mount_nfs 8 ,
|
|
for additional options that may be specified.
|
|
All options that can be given to the file system specific mount commands
|
|
can be used in
|
|
.Nm
|
|
as well.
|
|
They just need to be formatted a bit differently.
|
|
The arguments of the
|
|
.Fl o
|
|
option can be used without the preceding
|
|
.Fl o
|
|
flag.
|
|
Other options need both the file system specific flag and its argument,
|
|
separated by an equal sign.
|
|
For example, mounting an
|
|
.Xr msdosfs 5
|
|
filesystem, the options
|
|
.Bd -literal -offset indent
|
|
-o sync -o noatime -m 644 -M 755 -u foo -g bar
|
|
.Ed
|
|
.Pp
|
|
should be written as
|
|
.Bd -literal -offset indent
|
|
sync,noatime,-m=644,-M=755,-u=foo,-g=bar
|
|
.Ed
|
|
.Pp
|
|
in the option field of
|
|
.Nm .
|
|
.Pp
|
|
If the options ``userquota'' and/or ``groupquota'' are specified,
|
|
the file system is automatically processed by the
|
|
.Xr quotacheck 8
|
|
command, and user and/or group disk quotas are enabled with
|
|
.Xr quotaon 8 .
|
|
By default,
|
|
file system quotas are maintained in files named
|
|
.Pa quota.user
|
|
and
|
|
.Pa quota.group
|
|
which are located at the root of the associated file system.
|
|
These defaults may be overridden by putting an equal sign
|
|
and an alternative absolute pathname following the quota option.
|
|
Thus, if the user quota file for
|
|
.Pa /tmp
|
|
is stored in
|
|
.Pa /var/quotas/tmp.user ,
|
|
this location can be specified as:
|
|
.Bd -literal -offset indent
|
|
userquota=/var/quotas/tmp.user
|
|
.Ed
|
|
.Pp
|
|
If the option ``noauto'' is specified, the file system will not be automatically
|
|
mounted at system startup.
|
|
Note that, for network file systems
|
|
of third party types
|
|
(i.e., types supported by additional software
|
|
not included in the base system)
|
|
to be automatically mounted at system startup,
|
|
the
|
|
.Va extra_netfs_types
|
|
.Xr rc.conf 5
|
|
variable must be used to extend the
|
|
.Xr rc 8
|
|
startup script's list of network file system types.
|
|
.Pp
|
|
The type of the mount is extracted from the
|
|
.Fa fs_mntops
|
|
field and stored separately in the
|
|
.Fa fs_type
|
|
field (it is not deleted from the
|
|
.Fa fs_mntops
|
|
field).
|
|
If
|
|
.Fa fs_type
|
|
is ``rw'' or ``ro'' then the file system whose name is given in the
|
|
.Fa fs_file
|
|
field is normally mounted read-write or read-only on the
|
|
specified special file.
|
|
If
|
|
.Fa fs_type
|
|
is ``sw'' then the special file is made available as a piece of swap
|
|
space by the
|
|
.Xr swapon 8
|
|
command at the end of the system reboot procedure.
|
|
The fields other than
|
|
.Fa fs_spec
|
|
and
|
|
.Fa fs_type
|
|
are unused.
|
|
If
|
|
.Fa fs_type
|
|
is specified as ``xx'' the entry is ignored.
|
|
This is useful to show disk partitions which are currently unused.
|
|
.Pp
|
|
The fifth field,
|
|
.Pq Fa fs_freq ,
|
|
is used for these file systems by the
|
|
.Xr dump 8
|
|
command to determine which file systems need to be dumped.
|
|
If the fifth field is not present, a value of zero is returned and
|
|
.Nm dump
|
|
will assume that the file system does not need to be dumped.
|
|
If the fifth field is greater than 0, then it specifies the number of days
|
|
between dumps for this file system.
|
|
.Pp
|
|
The sixth field,
|
|
.Pq Fa fs_passno ,
|
|
is used by the
|
|
.Xr fsck 8
|
|
and
|
|
.Xr quotacheck 8
|
|
programs to determine the order in which file system and quota
|
|
checks are done at reboot time.
|
|
The
|
|
.Fa fs_passno
|
|
field can be any value between 0 and
|
|
.Ql INT_MAX Ns -1 .
|
|
.Pp
|
|
The root file system should be specified with a
|
|
.Fa fs_passno
|
|
of 1, and other file systems should have a
|
|
.Fa fs_passno
|
|
of 2 or greater.
|
|
A file system with a
|
|
.Fa fs_passno
|
|
value of 1 is always checked sequentially and be completed before
|
|
another file system is processed, and it will be processed before
|
|
all file systems with a larger
|
|
.Fa fs_passno .
|
|
.Pp
|
|
For any given value of
|
|
.Fa fs_passno ,
|
|
file systems within a drive will be checked sequentially,
|
|
but file systems on different drives will be checked at the
|
|
same time to utilize parallelism available in the hardware.
|
|
Once all file system checks are complete for the current
|
|
.Fa fs_passno ,
|
|
the same process will start over for the next
|
|
.Fa fs_passno .
|
|
.Pp
|
|
If the sixth field is not present or is zero,
|
|
a value of zero is returned and
|
|
.Xr fsck 8
|
|
and
|
|
.Xr quotacheck 8
|
|
will assume that the file system does not need to be checked.
|
|
.Pp
|
|
The
|
|
.Fa fs_passno
|
|
field can be used to implement finer control when
|
|
the system utilities may determine that the file system resides
|
|
on a different physical device, when it actually does not, as with a
|
|
.Xr ccd 4
|
|
device.
|
|
All file systems with a lower
|
|
.Fa fs_passno
|
|
value will be completed before starting on file systems with a
|
|
higher
|
|
.Fa fs_passno
|
|
value.
|
|
E.g. all file systems with a
|
|
.Fa fs_passno
|
|
of 2 will be completed before any file systems with a
|
|
.Fa fs_passno
|
|
of 3 or greater are started.
|
|
Gaps are allowed between the different
|
|
.Fa fs_passno
|
|
values.
|
|
E.g. file systems listed in
|
|
.Pa /etc/fstab
|
|
may have
|
|
.Fa fs_passno
|
|
values such as 0, 1, 2, 15, 100, 200, 300, and may appear in any order
|
|
within
|
|
.Pa /etc/fstab .
|
|
.Bd -literal
|
|
#define FSTAB_RW "rw" /* read/write device */
|
|
#define FSTAB_RQ "rq" /* read/write with quotas */
|
|
#define FSTAB_RO "ro" /* read-only device */
|
|
#define FSTAB_SW "sw" /* swap device */
|
|
#define FSTAB_XX "xx" /* ignore totally */
|
|
|
|
struct fstab {
|
|
char *fs_spec; /* block special device name */
|
|
char *fs_file; /* file system path prefix */
|
|
char *fs_vfstype; /* File system type, ufs, nfs */
|
|
char *fs_mntops; /* Mount options ala -o */
|
|
char *fs_type; /* FSTAB_* from fs_mntops */
|
|
int fs_freq; /* dump frequency, in days */
|
|
int fs_passno; /* pass number on parallel fsck */
|
|
};
|
|
.Ed
|
|
.Pp
|
|
The proper way to read records from
|
|
.Pa fstab
|
|
is to use the routines
|
|
.Xr getfsent 3 ,
|
|
.Xr getfsspec 3 ,
|
|
.Xr getfstype 3 ,
|
|
and
|
|
.Xr getfsfile 3 .
|
|
.Sh FILES
|
|
.Bl -tag -width /etc/fstab -compact
|
|
.It Pa /etc/fstab
|
|
The file
|
|
.Nm
|
|
resides in
|
|
.Pa /etc .
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr getfsent 3 ,
|
|
.Xr getvfsbyname 3 ,
|
|
.Xr ccd 4 ,
|
|
.Xr dump 8 ,
|
|
.Xr fsck 8 ,
|
|
.Xr mount 8 ,
|
|
.Xr quotacheck 8 ,
|
|
.Xr quotaon 8 ,
|
|
.Xr swapon 8 ,
|
|
.Xr umount 8
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
file format appeared in
|
|
.Bx 4.0 .
|