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fsave(ADM)

fsphoto(ADM)

xbackup(ADM)


 schedule(ADM)                   19 June 1992                   schedule(ADM)


 Name

    schedule - database for automated system backups

 Description

    The schedule database is used in conjunction with fsphoto(ADM) to par-
    tially automate system-wide backups.  For each filesystem to be backed
    up, a cyclical schedule of xbackup(ADM) or cpio(C) levels is specified.
    (fsphoto uses cpio for UNIX filesystems and xbackup for XENIX file-
    systems.)

    This cyclical schedule (or ``cycle'') is a list of backup levels to per-
    form (including no backup at all) and a pointer to the last-used element
    of that list.  The pointer is advanced to the next element of the list on
    a regular basis (each time fsphoto is run, usually once per day), start-
    ing at the beginning each time it falls off the end.  It is advanced,
    however, only on success -- the desired backup must have been successful.

    Each entry in the file is on a separate line.  Blank and comment lines
    (beginning with ``#'') may be placed anywhere.  Several keywords are
    recognized:

    site sitename
         sitename is passed to fsave(ADM) as a description to place on each
         tape label.  Usually, sitename is the name of the company or a
         building number.

    media drive k size [ size... ] [format]
         Device drive is a floppy disk or tape drive capable of handling vol-
         umes with any of the listed sizes (in kilobytes).  If specified,
         format is the command used to format the described floppies.  This
         also applies to standard cartridge tapes.

    media drive d density size [ size... ] [ format ]
         Device drive is a density BPI magtape drive capable of handling
         tapes of any of the indicated sizes (in feet).  As with floppy
         drives, format is the optional command used to format the described
         tape.

    [0-9] size savetime importance marker
         Description of each backup level, as described in fsave(ADM).  The
         defaults are:
         Level   Size    Savetime        Importance      Marker
          0       -      "1 year"        critical        none
          1       -      "3 months"      necessary       none
          2...7   -      "1 month"       important       none
          8       -      "2 weeks"       useful          none
          9       -      "1 week"        precautionary   none

         All four fields must be specified.  A size means to use the first
         size listed in the appropriate media sizes list.

    Keywords should be placed before any filesystem backup schedules.  A
    filesystem backup schedule is of the form:

    /dev/rfilesys cycle
         The filesystem resident on device /dev/filesys is to be backed-up
         according to cycle, which is a space-separated list of backup levels
         (the digits 0 to 9, passed to backup), or the letter x, meaning no
         backup should occur.

         A backup cycle must have at least one member, but it may be of any
         length.  Different filesystems may have cycles of different lengths.

    Here is the default schedule file:

    # SYSTEM BACKUP SCHEDULE
    site machinename

    # Media Entries
    #
    # 96 tpi 1.2 MB floppy 0
    media /dev/rfd096ds15 k 1200 format /dev/rfd096ds15
    # 96 tpi 1.2 MB floppy 1
    media /dev/rfd196ds15 k 1200 format /dev/rfd196ds15
    # 135 tpi 1.44 MB floppy 0
    media /dev/rfd0135ds18 k 1440 format /dev/rfd0135ds18
    # 135 tpi 1.44 MB floppy 1
    media /dev/rfd1135ds18 k 1440 format /dev/rfd1135ds18
    # Cartridge tape 1
    # media /dev/rct0 k 60000 125000 150000 tape erase
    # Mini cartridge drive (10 MB)
    # media /dev/rctmini k 8800 format /dev/rctmini
    # Mini cartridge drive (20 MB)
    # media /dev/rctmini k 17200 format /dev/rctmini
    # Mini cartridge drive (40 MB)
    # media /dev/rctmini k 37500 format /dev/rctmini
    # 9-track tape drive
    # media /dev/rmt0 d 1600 2400 1200 600
    #
    # Backup Descriptor Table
    #        Backup   Vol.   Save for    Vitality        Label
    #        level    size   how long    (importance)    marker
             0        -      "1 year"    critical        "a red sticker"
             1        -      "4 months"  necessary       "a yellow sticker"
             2        -      "3 weeks"   useful          "a blue sticker"
             3        -      "1 week"    precautionary   none
    # Schedule table
    #                 1 2 3 4 5    6 7 8 9 0    1 2 3 4 5    6 7 8 9 0
    # Filesystem      M T W T F    M T W T F    M T W T F    M T W T F Method
    /dev/rroot        0 3 3 3 3    2 3 3 3 3    1 3 3 3 3    2 3 3 3 3 cpio
    # Alternative Schedule for systems with /u filesystems
    # /dev/rroot      0 x 3 x 3    2 x 3 x 3    1 x 3 x 3    2 x 3 x 3 cpio
    # /dev/ru         3 0 3 3 3    3 2 3 3 3    3 1 3 3 3    3 2 3 3 3 cpio

    In the first example (no additional filesystems), /dev/rroot is backed up
    each day.  Once a month a level 0 is done, and level 3 backups are done
    on most days.  Each following Monday, a level 1 or 2 is done to ensure
    full redundancy.

    In the alternate example, /dev/rroot is backed-up using a level 0 backup
    the first time fsphoto is run (on a Monday), and if that backup is suc-
    cessful, the next (second) time it runs (Tuesday), no backup is per-
    formed.  If doing nothing is successful, the third time it runs (Wednes-
    day) a level 3 backup occurs.  If that backup succeeds, no backup occurs
    the fourth time (Thursday), but the fifth time fsphoto is run (Friday), a
    level 3 backup is made.

    Each time a successful backup at the specified level happens, the pointer
    advances so that the next run of fsphoto (on the next weekday) will do
    the next backup scheduled for that filesystem.  If however, a backup
    fails (or is interrupted or postponed by the operator) the pointer is not
    advanced; hence, the next time fsphoto is attempted, the same level
    backup will again be tried so the sequence will not be broken (but the
    timing may be off).

    The larger and more rapidly changing filesystem /dev/ru is backed up more
    frequently (each time fsphoto is run - once a day - instead of every
    other time), and the levels used are staggered to prevent having to per-
    form two full-scale backups (like levels 0 or 1) of the large filesystems
    on the same day.  The backup cycle period is also shorter, two weeks
    instead of four.

    The ``Method'' field defines the backup utility to be used. cpio works
    for both XENIX and UNIX filesystems, but xbackup works only on XENIX
    filesystems.

 See also

    fsave(ADM), fsphoto(ADM), xbackup(ADM)

 Notes

    Keywords and filesystem names must not be preceded by any spaces or tabs.

    It is not necessary to specify the name of the ``raw'' (/dev/r*) device
    for each filesystem, but the backups are faster if this is done.

 Value added

    schedule is an extension of AT&T System V provided by The Santa Cruz
    Operation, Inc.


Typewritten Software • bear@typewritten.org • Edmonds, WA 98026