Manual page for FSTAB(5)
fstab, mtab - static file system mounting table, mounted file systems table
SYNOPSIS
/etc/fstab
/etc/mtab
DESCRIPTION
The
/etc/fstab
file contains entries for file systems and disk partitions to mount
using the
mount.8
command, which is normally invoked by the
rc.boot
script at boot time.
This file is used by various utilities that
mount, unmount, check the consistency of, dump, and restore file systems.
It is also used by the system itself when locating the swap partition.
The
/etc/mtab
file contains entries for file systems
currently
mounted, and is read by programs using the routines described in
getmntent.3
umount.8
removes entries from this file;
mount
adds entries to this file.
Each entry consists of a line of the form:
filesystem directory type options freq pass
- filesystem
-
is the pathname of a block-special device, the name of a remote
file system in
host:pathname
form, or the name of a ``swap file'' made with
mkfile.8
- directory
-
is the pathname of the directory on which to mount the file system.
- type
-
is the file system type, which can be one of:
-
-
- 4.2
-
to mount a block-special device
- lo
-
to loopback-mount a file system
- nfs
-
to mount an exported
NFS
file system
- swap
-
to indicate a swap partition
- ignore
-
to have the
mount
command ignore the current entry (good
for noting disk partitions that are not being used)
- rfs
-
to mount an
RFS
file system
- tmp
-
file system in virtual memory
- hsfs
-
to mount an
ISO
9660 Standard or High Sierra Standard with Rock Ridge extensions
CD-ROM
file system
- options
-
contains a comma-separated list (no spaces) of mounting options,
some of which can be applied to all types of file systems, and
others which only apply to specific types.
-
4.2
options:
-
- quota|noquota
-
Disk quotas are enforced or not enforced.
The default is
noquota.
nfs
options:
-
- bg|fg
-
If the first attempt fails, retry in the background, or,
in the foreground.
- noquota
-
Prevent
quota.1
from checking whether the user is over quota on this file system;
if the file system has quotas enabled on the server, quotas will still
be checked for operations on this file system.
- retry=n
-
The number of times to retry the mount operation.
- rsize=n
-
Set the read buffer size to
n
bytes.
- wsize=n
-
Set the write buffer size to
n
bytes.
- timeo=n
-
Set the
NFS
timeout to
n
tenths of a second.
- retrans=n
-
The number of
NFS
retransmissions.
- port=n
-
The server
IP
port number.
- soft|hard
-
Return an error if the server does not
respond, or continue the
retry request until the server responds.
- intr
-
Allow keyboard interrupts on hard mounts.
- secure
-
Use a more secure protocol for
NFS
transactions.
- acregmin=n
-
Hold cached attributes for at least
n
seconds after file modification.
- acregmax=n
-
Hold cached attributes for no more than
n
seconds after file modification.
- acdirmin=n
-
Hold cached attributes for at least
n
seconds after directory update.
- acdirmax=n
-
Hold cached attributes for no more than
n
seconds after directory update.
- actimeo=n
-
Set
min
and
max
times for regular files and directories to
n
seconds.
- noac
-
Suppress attribute caching.
Regular defaults are:
-
fg,retry=10000,timeo=7,retrans=3,port=NFS_PORT,hard,\
acregmin=3,acregmax=60,acdirmin=30,acdirmax=60
actimeo
has no default; it sets
acregmin,
acregmax,
acdirmin
and
acdirmax
Defaults for
rsize
and
wsize
are set internally by the system kernel.
rfs
options:
-
- bg|fg
-
If the first attempt fails, retry in the background, or,
in the foreground.
- retry=n
-
The number of times to retry the mount operation.
Defaults are the same as for NFS.
hsfs
options:
-
- norrip
-
Disable processing of Rock Ridge extensions for the file system.
Common options:
-
- ro|rw
-
mount either read-only or read-write
- suid|nosuid
-
setuid execution allowed or disallowed
- grpid
-
Create files with
BSD
semantics for propagation of the group
ID.
With this option, files inherit the group
ID
of the directory in
which they are created, regardless of the directory's setgid bit.
- noauto
-
Do not mount this file system automatically (using
`mount -a').
- freq
-
is the interval (in days) between dumps.
- pass
-
indicates whether
fsck.8
should check the partition.
File systems with
pass
0 are not checked.
When preening the file systems in
/etc/fstab,
fsck.8
automatically overlaps file system checks
by simultaneously running one process per disk.
If run in ``force'' mode (-f), fsck
checks file systems with pass 1 sequentially,
then overlaps the remainder of the file systems checks.
In general, only the root (/) and /usr file systems need to be
checked in pass 1, with others checked in the second pass.
A hash-sign
(#)
as the first character indicates a comment line which
is ignored by routines that read this file.
The order of records in
/etc/fstab
is important because
fsck,
mount,
and
umount
process the file sequentially; an entry for a file system must appear
after
the entry for any file system it is to be mounted on top of.
EXAMPLES
In this example, two partitions on the local disk are
4.2
mounted. Several
/export
directories are loopback mounted to appear in
the traditional file system locations on the local system. The
/home/user
directory is hard mounted read-write over the
NFS,
along with additional swap space in the form of a mounted swap file
(see
System and Network Administration
for details on adding swap space):
-
/dev/xy0a / 4.2 rw,noquota 1 1
/dev/xy0b /usr 4.2 rw,noquota 1 1
/export/tmp/localhost /tmp lo rw 0 0
/export/var/localhost /var lo rw 0 0
/export/cluster/sun386.sunos4.0.1 /usr/cluster lo rw 0 0
/export/local/sun386 /usr/local lo rw 0 0
example:/home/user /home/user nfs rw,hard,fg 0 0
/export/swap/myswap swap swap rw 0 0
FILES
- /etc/fstab
-
- /etc/mtab
-
SEE ALSO
swapon.2
getmntent.3
lofs.4s
fsck.8
mkfile.8
mount.8
quotacheck.8
quotaon.8
swapon.8
System and Network Administration
Created by unroff & hp-tools.
© somebody (See intro for details). All Rights Reserved.
Last modified 11/5/97