FSTAB(5)						     Linux Programmer's Manual							  FSTAB(5)

NAME

       fstab - static information about the filesystems

SYNOPSIS

       #include <fstab.h>

DESCRIPTION

       The file fstab contains descriptive information about the various file systems.	fstab is only read by programs, and not written; it is the
       duty of the system administrator to properly create and maintain this file.  Each filesystem is described on a  separate  line;	fields	on
       each  line  are	separated  by  tabs  or spaces.  Lines starting with '#' are comments.	The order of records in fstab is important because
       fsck(8), mount(8), and umount(8) sequentially iterate through fstab doing their thing.

       The first field, (fs_spec), describes the block special device or remote filesystem to be mounted.

       For ordinary mounts it will hold (a link to) a block special device node (as created by mknod(8))  for  the  device  to	be  mounted,  like
       `/dev/cdrom' or `/dev/sdb7'.  For NFS mounts one will have <host>:<dir>, e.g., `knuth.aeb.nl:/'.  For procfs, use `proc'.

       Instead	of  giving  the device explicitly, one may indicate the (ext2 or xfs) filesystem that is to be mounted by its UUID or volume label
       (cf.  e2label(8) or xfs_admin(8)), writing LABEL=<label> or UUID=<uuid>, e.g., `LABEL=Boot' or `UUID=3e6be9de-8139-11d1-9106-a43f08d823a6'.
       This will make the system more robust: adding or removing a SCSI disk changes the disk device name but not the filesystem volume label.

       The  second field, (fs_file), describes the mount point for the filesystem.  For swap partitions, this field should be specified as `none'.
       If the name of the mount point contains spaces these can be escaped as `40'.

       The third field, (fs_vfstype), describes the type of the filesystem.  Linux supports lots of filesystem types, such as adfs, affs,  autofs,
       coda,  coherent,  cramfs,  devpts,  efs,  ext2, ext3, hfs, hpfs, iso9660, jfs, minix, msdos, ncpfs, nfs, ntfs, proc, qnx4, reiserfs, romfs,
       smbfs, sysv, tmpfs, udf, ufs, umsdos, vfat, xenix, xfs, and possibly others. For more details, see mount(8).  For the filesystems currently
       supported  by the running kernel, see /proc/filesystems.  An entry swap denotes a file or partition to be used for swapping, cf. swapon(8).
       An entry ignore causes the line to be ignored.  This is useful to show disk partitions which are currently unused.

       The fourth field, (fs_mntops), describes the mount options associated with the filesystem.

       It is formatted as a comma separated list of options.  It contains at least the type of mount plus any additional  options  appropriate	to
       the filesystem type.  For documentation on the available options for non-nfs file systems, see mount(8).  For documentation on all nfs-spe-
       cific options have a look at nfs(5).  Common for all types of file system are the options ``noauto'' (do  not  mount  when  "mount  -a"	is
       given, e.g., at boot time), ``user'' (allow a user to mount), and ``owner'' (allow device owner to mount), and ``_netdev'' (device requires
       network to be available).  The ``owner'' and ``_netdev'' options are Linux-specific.  For more details, see mount(8).

       The fifth field, (fs_freq), is used for these filesystems by the dump(8) command to determine which filesystems need to be dumped.  If  the
       fifth field is not present, a value of zero is returned and dump will assume that the filesystem does not need to be dumped.

       The  sixth  field,  (fs_passno),  is used by the fsck(8) program to determine the order in which filesystem checks are done at reboot time.
       The root filesystem should be specified with a fs_passno of 1, and other filesystems should have a fs_passno of 2.   Filesystems  within  a
       drive  will  be checked sequentially, but filesystems on different drives will be checked at the same time to utilize parallelism available
       in the hardware.  If the sixth field is not present or zero, a value of zero is returned and fsck will assume that the filesystem does  not
       need to be checked.

       The proper way to read records from fstab is to use the routines getmntent(3).

FILES

       /etc/fstab

SEE ALSO

       getmntent(3), mount(8), swapon(8), fs(5) nfs(5)

HISTORY

       The ancestor of this fstab file format appeared in 4.0BSD.

Linux 2.2							   15 June 1999 							  FSTAB(5)