FSTAB(5)                COMMAND REFERENCE                FSTAB(5)



NAME
     fstab - static information about file systems

SYNOPSIS
     #include <mntent.h>

DESCRIPTION
     The file /etc/fstab describes the file systems and swapping
     partitions used by the local machine. It is created by the
     system administrator using a text editor and processed by
     commands that mount, unmount, check consistency of, dump and
     restore file systems, and by the system in providing swap
     space.

     The fstab file consists of a number of lines of the form:

          fsname dir type opts freq passno

     An example of the file is

          /dev/xy0a / 4.2 rw,noquota 1 2

     The entries in the /etc/fstab file are accessed using the
     routines in getmntent(3), which returns a structure of the
     form:

          struct mntent {
                 char  *mnt_fsname;  /* file system name */
                 char  *mnt_dir;     /* file system path prefix */
                 char  *mnt_type;    /* 4.2, nfs, swap, or ignore */
                 char  *mnt_opts;    /* ro, quota, etc. */
                 int   mnt_freq;     /* dump frequency, in days */
                 int   mnt_passno;   /* pass number on parallel fsck */
          };

     There is one entry per line in the file, and the fields are
     separated by white space.  A `#' as the first character
     indicates a comment.

          Note 1:  No white space is allowed on the comment line
          before the comment begins.

          Note 2:  All six fields are required. Any line with
          less than six fields causes the mount -a command to
          quit, parsing the file at that point.

     The opts field consists of a string of comma-separated
     options. Some of the options are common to all file system
     types, others only make sense for a single file system type.
     See mount(8) for a more complete description of the options
     available.




Printed 3/13/89                                                 1

FSTAB(5)                COMMAND REFERENCE                FSTAB(5)



     The type field determines how the fsname and opts fields are
     interpreted. File system types currently supported and the
     way each of them interprets these fields is listed here:

     4.2:

        fsname      Must be a block special device.

        opts        Valid opts are ro, rw, suid, nosuid, quota,
                    and noquota.

     NFS:

        fsname      The path on the server of the directory to be
                    served.

        opts        Valid opts are ro, rw, suid, nosuid, hard,
                    soft, bg, fg, retry, rsize, wsize, timeo,
                    retrans, port, and intr.

     SWAP:

        fsname      Must be a block special device swap
                    partition.

        opts        Ignored.

     The opts are interpreted as follows:

        rw          read/write

        ro          read only

        suid        set uid execution allowed

        nosuid      set uid execution not allowed

        quota       usage limits enforced

        noquota     usage limits not enforced

        bg          if the first attempt fails, retry in the
                    background

        retry=n     set number of failure retries to n

        rsize=n     set read buffer size to n bytes

        wsize=n     set write buffer size to n bytes

        timeo=n     set NFS timeout to n tenths of a second




Printed 3/13/89                                                 2

FSTAB(5)                COMMAND REFERENCE                FSTAB(5)



        retrans=n   set number of NFS retransmissions to n

        port=n      set server IP port number to n

        soft        return error of server doesn't respond

        hard        retry request until server responds

     If the type is specified as ``ignore'' the entry is ignored.
     (This is useful to show disk partitions which are currently
     not used.)

     The field freq indicates how often each partition should be
     dumped by the dump(8) command (and triggers that command's w
     option which specifies which file systems should be dumped).
     Most systems set the freq field to 1 indicating that the
     file systems are dumped each day.

     The final field, passno, is used by the disk consistency
     check program fsck(8) to allow overlapped checking of file
     systems during a reboot.  All file systems with passno of 1
     are first checked simultaneously, then all file systems with
     passno of 2 are checked, and so on.  It is usual to make the
     passno of the root file system have the value 1 and then
     check one file system on each available disk drive in each
     subsequent pass to the exhaustion of file system partitions.

     The file /etc/fstab is only read by programs, and not
     written; it is the duty of the system administrator to
     properly create and maintain this file.  The order of
     records in /etc/fstab is important because fsck, mount, and
     umount process the file sequentially; file systems must
     appear after file systems they are mounted within.

FILES
     /etc/fstab

CAVEATS
     You MUST have information in all six fields. Any line with
     less than six fields causes the mount -a command to quit,
     parsing the file at that point.

SEE ALSO
     fsck(8), getmntent(3), mount(8), umount(8), and vifstab(8).











Printed 3/13/89                                                 3

%%index%%
na:264,97;
sy:361,295;
de:656,2502;3494,2957;6787,1925;
fi:8712,89;
ca:8801,313;
se:9114,224;
%%index%%000000000127