dump(1M)																  dump(1M)

NAME

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

SYNOPSIS

       [option [argument ...]  filesystem]

       [option [argument ...]  filesystem]

DESCRIPTION

       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.

   Options
	      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 defined 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 calculating the amount of tape used per reel.  The default 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 system 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 immediately.

	      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 written.

       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 interact 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 permission, 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 typically low estimates of the number of blocks  to  write,  the	number	of
       tapes  it  will	require,  the time needed for completion, and the time remaining 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 acl(5)).

EXAMPLES

       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.

WARNINGS

       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 files.

AUTHOR

       and were developed by the University of California, Berkeley.

FILES

       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

SEE ALSO

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

																	  dump(1M)