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       fstab - static information about the filesystems


       #include <fstab.h>


       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

       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., ‘’.  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 ‘\040’.

       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.  An entry none is useful
       for bind or move mounts.

       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-specific
       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  ‘‘comment’’  (e.g.,  for  use  by  fstab-
       maintaining  programs).   The  ‘‘owner’’  and  ‘‘comment’’  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), mount(8), swapon(8), fs(5), nfs(5)


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


       This man page is part of the util-linux-ng  package  and  is  available