dump(8) - ext2/3/4 filesystem backup
-a     “auto-size”.  Bypass  all  tape length calculations, and write until an end-of-media indication is
       returned.  This works best for most modern tape drives, and is the default. Use of this option  is
       particularly  recommended  when appending to an existing tape, or using a tape drive with hardware
       compression (where you can never be sure about the compression ratio).
-A archive_file
       Archive a dump table-of-contents in the  specified  archive_file  to  be  used  by  restore(8)  to
       determine whether a file is in the dump file that is being restored.
-b blocksize
       The  number  of  kilobytes  per dump record. The default blocksize is 10, unless the -d option has
       been used to specify a tape density of 6250BPI or more, in which case the default blocksize is 32.
       Th  maximal value is 1024.  Note however that, since the IO system slices all requests into chunks
       of MAXBSIZE (which can be as low as 64kB), you can experience problems with dump(8) and restore(8)
       when using a higher value, depending on your kernel and/or libC versions.
-B records
       The number of 1 kB blocks per volume. Not normally required, as dump can detect end-of-media. When
       the specified size is reached, dump waits for you to change the volume.  This option overrides the
       calculation of tape size based on length and density. If compression is on this limits the size of
       the compressed output per volume.  Multiple values may be given as a single argument separated  by
       commas.   Each  value  will  be used for one dump volume in the order listed; if dump creates more
       volumes than the number of values given, the last value will be used for  the  remaining  volumes.
       This  is  useful for filling up already partially filled media (and then continuing with full size
       volumes on empty media) or mixing media of different sizes.
-c     Change the defaults for use with a cartridge tape drive, with a density of 8000 bpi, and a  length
       of 1700 feet. Specifying a cartridge drive overrides the end-of-media detection.
-d density
       Set tape density to density.  The default is 1600BPI. Specifying a tape density overrides the end-
       of-media detection.
-D file
       Set the path name of the file storing the information about  the  previous  full  and  incremental
       dumps. The default location is /var/lib/dumpdates.
-e inodes
       Exclude inodes from the dump. The inodes parameter is a comma separated list of inode numbers (you
       can use stat(1) to find the inode number for a file or directory).
-E file
       Read list of inodes to be excluded from the dump from the text file file.  The file file should be
       an ordinary file containing inode numbers separated by newlines.
-f file
       Write  the  backup  to  file;  file  may  be  a  special device file like /dev/st0 (a tape drive),
       /dev/rsd1c (a floppy disk drive), an ordinary file, or -  (the  standard  output).  Multiple  file
       names  may  be given as a single argument separated by commas. Each file will be used for one dump
       volume in the order listed; if the dump requires more volumes than the number of names given,  the
       last  file name will used for all remaining volumes after prompting for media changes. If the name
       of the file is of the form host:file or user@host:file dump writes to the named file on the remote
       host  (which  should  already  exist,  dump  doesn't  create a new remote file) using rmt(8).  The
       default path name of the remote rmt(8)  program  is  /etc/rmt;  this  can  be  overridden  by  the
       environment variable RMT.
-F script
       Run  script  at  the  end of each tape (except for the last one).  The device name and the current
       volume number are passed on the command line. The script must return 0  if  dump  should  continue
       without  asking  the user to change the tape, 1 if dump should continue but ask the user to change
       the tape. Any other exit code will cause dump to abort. For security reasons, dump reverts back to
       the real user ID and the real group ID before running the script.
-h level
       Honor  the  user  nodump  flag  UF_NODUMP only for dumps at or above the given level.  The default
       honor level is 1, so that incremental backups omit such files but full backups retain them.
-I nr errors
       By default, dump will ignore the first 32 read  errors  on  the  file  system  before  asking  for
       operator  intervention.  You  can  change  this  using this flag to any value. This is useful when
       running dump on an active filesystem where read errors simply indicate  an  inconsistency  between
       the mapping and dumping passes.

       A value of 0 means that all read errors will be ignored.
-jcompression level
       Compress  every  block  to  be written on the tape using bzlib library. This option will work only
       when dumping to a file or pipe or, when dumping to a tape drive, if the tape drive is  capable  of
       writing  variable  length blocks. You will need at least the 0.4b24 version of restore in order to
       extract compressed tapes. Tapes written using compression will not be compatible with the BSD tape
       format.  The  (optional)  parameter  specifies  the  compression level bzlib will use. The default
       compression level is 2. If the optional parameter is specified, there should  be  no  white  space
       between the option letter and the parameter.
-k     Use  Kerberos  authentication  to  talk to remote tape servers. (Only available if this option was
       enabled when dump was compiled.)
-L label
       The user-supplied text string label is placed into the dump header, where  tools  like  restore(8)
       and  file(8)  can  access it. Note that this label is limited to be at most LBLSIZE (currently 16)
       characters, which must include the terminating \0.
-m     If this flag is specified, dump will optimise the output for inodes having been  changed  but  not
       modified  since the last dump ('changed' and 'modified' have the meaning defined in stat(2) ). For
       those inodes, dump will save only the metadata, instead  of  saving  the  entire  inode  contents.
       Inodes  which  are  either  directories  or  have been modified since the last dump are saved in a
       regular way. Uses of this  flag  must  be  consistent,  meaning  that  either  every  dump  in  an
       incremental dump set have the flag, or no one has it.

       If  you  use  this  option, be aware that many programs that unpack files from archives (e.g. tar,
       rpm, unzip, dpkg) may set files' mtimes to dates in the past.  Files installed in this way may not
       be dumped correctly using "dump -m" if the modified mtime is earlier than the previous level dump.

       Tapes written using such 'metadata only' inodes will not be compatible with the BSD tape format or
       older versions of restore.
-M     Enable the multi-volume feature. The name specified with f is treated as a prefix and dump  writes
       in  sequence  to  <prefix>001,  <prefix>002  etc.  This  can be useful when dumping to files on an
       ext2/3/4 partition, in order to bypass the 2GB file size limitation.
-n     Whenever dump requires operator attention, notify all operators in the  group  operator  by  means
       similar to a wall(1).
-q     Make  dump abort immediately whenever operator attention is required, without prompting in case of
       write errors, tape changes etc.
-Q file
       Enable the Quick File Access support. Tape positions for each inode are stored into the file  file
       which  is  used by restore (if called with parameter -Q and the filename) to directly position the
       tape at the file restore is currently working on. This saves hours  when  restoring  single  files
       from large backups, saves the tapes and the drive's head.

       It  is  recommended  to set up the st driver to return logical tape positions rather than physical
       before calling dump/restore with parameter -Q.  Since not all tape devices support  physical  tape
       positions  those tape devices return an error during dump/restore when the st driver is set to the
       default physical setting.  Please see the st(4) man page, option MTSETDRVBUFFER , or the mt(1) man
       page, on how to set the driver to return logical tape positions.

       Before calling restore with parameter -Q, always make sure the st driver is set to return the same
       type of tape position used during the call to dump.  Otherwise restore may be confused.

       This option can be used when dumping to local tapes (see above) or to local files.
-s feet
       Attempt to calculate the amount of tape  needed  at  a  particular  density.  If  this  amount  is
       exceeded,  dump prompts for a new tape. It is recommended to be a bit conservative on this option.
       The default tape length is 2300 feet. Specifying the tape size overrides end-of-media detection.
-S     Size estimate. Determine the amount of space that is needed to perform the dump  without  actually
       doing  it, and display the estimated number of bytes it will take. This is useful with incremental
       dumps to determine how many volumes of media will be needed.
-T date
       Use the specified date as the starting time for the dump  instead  of  the  time  determined  from
       looking in /var/lib/dumpdates .  The format of date is the same as that of ctime(3) followed by an
       rfc822 timezone specification: either a plus or minus sign followed by two digits for  the  number
       of  hours and two digits for the minutes.  For example, -0800 for eight hours west of Greenwich or
       +0230 for two hours and a half east of Greenwich. This timezone offset takes into account daylight
       savings  time (if applicable to the timezone): UTC offsets when daylight savings time is in effect
       will be different than offsets  when  daylight  savings  time  is  not  in  effect.  For  backward
       compatibility,  if  no  timezone is specified, a local time is assumed.  This option is useful for
       automated dump scripts that wish to dump over a specific period of time. The -T option is mutually
       exclusive from the -u option.
-u     Update  the  file  /var/lib/dumpdates after a successful dump. The format of /var/lib/dumpdates is
       readable by people, consisting of one free format record  per  line:  filesystem  name,  increment
       level and ctime(3) format dump date followed by a rfc822 timezone specification (see the -u option
       for details). If no timezone offset is specified, times are interpreted  as  local.  Whenever  the
       file  is written, all dates in the file are converted to the local time zone, without changing the
       UTC times. There may be only one entry per filesystem at each level. The  file  /var/lib/dumpdates
       may be edited to change any of the fields, if necessary.
-v     The -v (verbose) makes dump to print extra information which could be helpful in debug sessions.
-W     Dump  tells the operator what file systems need to be dumped. This information is gleaned from the
       files /var/lib/dumpdates and /etc/fstab.  The -W option causes dump to print  out,  for  all  file
       systems in /var/lib/dumpdates , and recognized file systems in /etc/mtab and /etc/fstab.  the most
       recent dump date and level, and highlights those that should be dumped. If the -W option  is  set,
       all other options are ignored, and dump exits immediately.
-w     Is  like  -W,  but prints only recognized filesystems in /etc/mtab and /etc/fstab which need to be
       dumped.
-y     Compress every block to be written to the tape using the lzo library.  This  doesn't  compress  as
       well  as the zlib library but it's much faster.  This option will work only when dumping to a file
       or pipe or, when dumping to a tape drive, if the tape drive is capable of writing variable  length
       blocks.   You  will  need  at  least  the 0.4b34 version of restore in order to extract compressed
       tapes. Tapes written using compression will not be compatible with the BSD tape format.
-zcompression level
       Compress every block to be written on the tape using zlib library. This option will work only when
       dumping  to  a  file  or  pipe  or,  when dumping to a tape drive, if the tape drive is capable of
       writing variable length blocks. You will need at least the 0.4b22 version of restore in  order  to
       extract compressed tapes. Tapes written using compression will not be compatible with the BSD tape
       format. The (optional) parameter specifies the  compression  level  zlib  will  use.  The  default
       compression  level  is  2.  If the optional parameter is specified, there should be no white space
       between the option letter and the parameter.