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dump(1M)							      dump(1M)

       dump, rdump - incremental file system dump, local or across network

       [option [argument ...]  filesystem]

       [option [argument ...]  filesystem]

       The and commands	copy to	magnetic tape all files	in the filesystem that
       have been changed after a certain date.	This  information  is  derived
       from  the  files	 and option specifies the date and other options about
       the dump.  option consists of characters	from the set The and  commands
       work  only  on  file systems of type If the given file system is	not of
       type and	will abort after printing an error message.

	      This number is the "dump level".
			All files modified since the last date stored in  file
			for  the  same	file  system  at lesser	levels will be
			dumped.	 If no date is determined by  the  level,  the
			beginning of time is assumed.  Thus, the option	causes
			the entire file	system to be dumped.

	      The blocking factor is taken from	the next argument
			(default is 10 if not specified).  Block size  is  de-
			fined  as  the	logical	record size times the blocking
			factor.	 writes	logical	records	of 1024	 bytes.	  When
			dumping	to tapes with densities	of 6250	BPI or greater
			without	using the option, the default blocking	factor
			is 32.

	      The density of the tape (expressed in BPIs)
			is taken from the next argument.  This is used in cal-
			culating the amount of tape used per  reel.   The  de-
			fault value of 1600 assumes a reel tape.

	      Place the	dump on	the next
			argument file instead of the tape.  If the name	of the
			file is	writes to the  standard	 output.   When	 using
			this option should be specified, and the next argument
			supplied should	be of the form

	      Whenever	and require operator attention,	notify	all  users  in
			group by means similar to that described by wall(1).

	      The size of the dump tape	is specified in	feet.
			The  number  of	 feet is taken from the	next argument.
			When the specified size	is reached, and	wait for reels
			to  be	changed.   The default tape size value of 2300
			feet assumes a reel tape.

	      If the dump completes successfully,
			write on file the date when the	 dump  started.	  This
			file  records a	separate date for each file system and
			each dump level.  The format of	is  user-readable  and
			consists of one	free-format record per line: file sys-
			tem name, increment level, and dump date in  ctime(3C)
			format.	  The  file can	be edited to change any	of the
			fields if necessary.

	      For each file system in
			print the most recent dump date	and level,  indicating
			which file systems should be dumped.  If the option is
			set, all other options are ignored and	exits  immedi-

	      Operates like
			but prints only	file systems that need to be dumped.

       If  no  arguments are given, option is assumed to be and	a default file
       system is dumped	to the default tape.

       Sizes are based on 1600-BPI blocked tape; the raw magnetic tape	device
       must  be	used to	approach these densities.  Up to 32 read errors	on the
       file system are ignored.	 Each reel requires a new process; thus	parent
       processes  for  reels  already  written remain until the	entire tape is

       The command creates a server, or	on the remote machine  to  access  the
       tape device.

       and require operator intervention for any of the	following conditions:

	      o	 end of	tape,
	      o	 end of	dump,
	      o	 tape-write error,
	      o	 tape-open error, or
	      o	 disk-read error (if errors exceed threshold of	32).

       In addition to alerting all operators implied by	the option, and	inter-
       act with	the control terminal operator by posing	questions requiring or
       answers when it can no longer proceed or	if something is	grossly	wrong.

       Since  making  a	 full  dump involves considerable time and effort, and
       each establish a	checkpoint at the start	of each	tape volume.  If,  for
       any  reason, writing that volume	fails, and will, with operator permis-
       sion, restart from the checkpoint after the old tape has	 been  rewound
       and removed and a new tape has been mounted.

       and  periodically  report  information to the operator, including typi-
       cally low estimates of the number of blocks to  write,  the  number  of
       tapes it	will require, the time needed for completion, and the time re-
       maining until tape change.  The output is verbose to inform other users
       that the	terminal controlling and is busy and will be for some time.

   Access Control Lists	(ACLs)
       The  optional  entries  of  a  file's access control list (ACL) are not
       backed up with and Instead, the file's permission bits  are  backed  up
       and  any	information contained in its optional ACL entries is lost (see

       In the following	example, assume	that the file system is	to be attached
       to  the file tree at the	root directory,	This example causes the	entire
       file system to be dumped	on and specifies that the density of the  tape
       is 6250 BPI.

       will not	backup a file system containing	large files.

       Tapes  created from file	systems	containing files with UID/GIDs greater
       than 60,000 will	have a new magic number	in the header to prevent older
       versions	of restore(1M) from incorrectly	restoring ownerships for these

       and were	developed by the University of California, Berkeley.

       Default file system to dump from.
       Default tape unit to dump to.
       New format-dump-date record.
       Dump table: file	systems	and frequency.
       Used to find group

       restore(1M), rmt(1M), fstab(4), acl(5).



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