/sys/doc/ Documentation archive

DUMP(VIII)                   11/24/73                  DUMP(VIII)

     dump - incremental file system dump

     dump [ key [ arguments ] filesystem ]

     Dump makes an incremental file system dump on magtape of all
     files changed after a certain date.  The key argument speci-
     fies  the  date  and other options about the dump.  Key con-
     sists of characters from the set abcfiu0hds.

     a    Normally files larger than 1000 blocks are  not  incre-
          mentally dump; this flag forces them to be dumped.

     b    The  next  argument  is taken to be the maximum size of
          the dump tape in blocks (see s).

     c    If the tape overflows, increment the last character  of
          its name and continue on that drive.  (Normally it asks
          you to change tapes.)

     f    Place the dump on the next argument file instead of the

     i    the  dump  date  is  taken  from  the entry in the file
          /etc/dtab corresponding to the last time this file sys-
          tem was dumped with the -u option.

     u    the  date  just  prior  to  this  dump  is  written  on
          /etc/dtab upon  successful  completion  of  this  dump.
          This  file contains a date for every file system dumped
          with this option.

     0    the dump date is  taken  as  the  epoch  (beginning  of
          time).   Thus  this option causes an entire file system
          dump to be taken.

     h    the dump date is some number of hours before  the  cur-
          rent  date.  The number of hours is taken from the next
          argument in arguments.

     d    the dump date is some number of days before the current
          date.   The number of days is taken from the next argu-
          ment in arguments.

     s    the size of the dump tape is specified  in  feet.   The
          number of feet is taken from the next argument in argu-
          ments.  It is assumed that there are  9  standard  UNIX
          records  per foot.  When the specified size is reached,
          the dump will wait for reels to be  changed.   The  de-
          fault size is 2200 feet.

     If  no  arguments  are given, the key is assumed to be i and
     the file system is assumed to be /dev/rp0.

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DUMP(VIII)                   11/24/73                  DUMP(VIII)

     Full dumps should be taken on quiet file systems as follows:

             dump 0u /dev/rp0
             ncheck /dev/rp0

     The ncheck will come in handy in case it is necessary to re-
     store individual files from this  dump.   Incremental  dumps
     should then be taken when desired by:


     When  the  incremental  dumps get cumbersome, a new complete
     dump should be taken.  In this way, a restore requires load-
     ing  of the complete dump tape and only the latest incremen-
     tal tape.

     If the dump requires more than one tape, it will ask you  to
     change  tapes.   Reply  with  a  new-line when this has been
     done.  If the first block on the new tape is  not  writable,
     e.g.  because you forgot the write ring, you get a chance to
     fix it.  Generally, however, read or write failures are  fa-

     /dev/mt0        magtape
     /dev/rp0        default file system

     restor(VIII), ncheck(VIII), dump(V)


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