Provided by: dump_0.4b44-7_amd64 bug


       restore - restore files or file systems from backups made with dump


       restore  -C  [-cdHklMvVy]  [-b blocksize] [-D filesystem] [-f file] [-F script] [-L limit]
       [-s fileno] [-T directory]

       restore -i [-acdhHklmMNouvVy] [-A file] [-b blocksize] [-f file] [-F script] [-Q file] [-s
       fileno] [-T directory]

       restore  -P  file  [-acdhHklmMNuvVy]  [-b blocksize] [-f file] [-F script] [-s fileno] [-T
       directory] [-X filelist] [ file ... ]

       restore -R [-cdHklMNuvVy] [-b blocksize] [-f file] [-F script] [-s fileno] [-T directory]

       restore -r [-cdHklMNuvVy] [-b blocksize] [-f file] [-F script] [-s fileno] [-T directory]

       restore -t [-cdhHklMNuvVy] [-A file] [-b blocksize] [-f file] [-F script]  [-Q  file]  [-s
       fileno] [-T directory] [-X filelist] [ file ... ]

       restore -x [-adchHklmMNouvVy] [-A file] [-b blocksize] [-f file] [-F script] [-Q file] [-s
       fileno] [-T directory] [-X filelist] [ file ... ]


       The restore command performs the inverse function of dump(8).  A full  backup  of  a  file
       system  may  be  restored  and subsequent incremental backups layered on top of it. Single
       files and directory subtrees may be restored from full or partial backups.  Restore  works
       across  a  network;  to  do  this  see the -f flag described below. Other arguments to the
       command are file or directory names specifying the files that are to be  restored.  Unless
       the  -h  flag  is  specified (see below), the appearance of a directory name refers to the
       files and (recursively) subdirectories of that directory.

       Exactly one of the following flags is required:

       -C     This mode allows comparison of files from a dump.  Restore  reads  the  backup  and
              compares  its contents with files present on the disk. It first changes its working
              directory to the root of the filesystem that was dumped and compares the tape  with
              the files in its new current directory. See also the -L flag described below.

       -i     This mode allows interactive restoration of files from a dump. After reading in the
              directory information from the dump, restore provides a shell like  interface  that
              allows  the user to move around the directory tree selecting files to be extracted.
              The available commands  are  given  below;  for  those  commands  that  require  an
              argument, the default is the current directory.

              add [arg]
                     The current directory or specified argument is added to the list of files to
                     be extracted.  If a directory is specified, then it and all its  descendents
                     are  added  to  the  extraction list (unless the -h flag is specified on the
                     command line). Files that are on the extraction list are  prepended  with  a
                     “*” when they are listed by ls.

              cd arg Change the current working directory to the specified argument.

              delete [arg]
                     The  current  directory  or  specified  argument is deleted from the list of
                     files to be extracted. If a directory is specified,  then  it  and  all  its
                     descendents  are  deleted  from  the  extraction list (unless the -h flag is
                     specified on the command line). The most expedient way to  extract  most  of
                     the  files  from  a directory is to add the directory to the extraction list
                     and then delete those files that are not needed.

                     All files on the extraction list are extracted from the dump.  Restore  will
                     ask which volume the user wishes to mount. The fastest way to extract a f ew
                     files is to start with the last volume and work towards the first volume.

              help   List a summary of the available commands.

              ls [arg]
                     List the current or specified directory. Entries that  are  directories  are
                     appended  with  a  “/”.  Entries  that  have  been marked for extraction are
                     prepended with a “*”. If the verbose flag is set, the inode number  of  each
                     entry is also listed.

              pwd    Print the full pathname of the current working directory.

              quit   Restore immediately exits, even if the extraction list is not empty.

                     All  directories  that  have  been  added  to the extraction list have their
                     owner, modes, and times set; nothing is extracted from  the  dump.  This  is
                     useful for cleaning up after a restore has been prematurely aborted.

                     The  sense  of the -v flag is toggled. When set, the verbose flag causes the
                     ls command to list the inode numbers of all entries. It also causes  restore
                     to print out information about each file as it is extracted.

       -P file
              Restore  creates  a  new  Quick  File  Access  file file from an existing dump file
              without restoring its contents.

       -R     Restore requests a particular tape of a multi-volume set on which to restart a full
              restore  (see  the  -r  flag  below).  This  is  useful  if  the  restore  has been

       -r     Restore (rebuild) a file system. The target file system  should  be  made  pristine
              with  mke2fs(8),  mounted,  and  the user cd'd into the pristine file system before
              starting the restoration of the initial level 0 backup. If  the  level  0  restores
              successfully,  the -r flag may be used to restore any necessary incremental backups
              on top of the level 0. The -r flag precludes an interactive file extraction and can
              be  detrimental to one's health (not to mention the disk) if not used carefully. An

                     mke2fs /dev/sda1

                     mount /dev/sda1 /mnt

                     cd /mnt

                     restore rf /dev/st0

              Note that restore leaves a file restoresymtable  in  the  root  directory  to  pass
              information  between  incremental restore passes.  This file should be removed when
              the last incremental has been restored.

              Restore, in conjunction with mke2fs(8) and dump(8), may  be  used  to  modify  file
              system parameters such as size or block size.

       -t     The names of the specified files are listed if they occur on the backup. If no file
              argument is given, the root directory  is  listed,  which  results  in  the  entire
              content  of  the  backup being listed, unless the -h flag has been specified.  Note
              that the -t flag replaces the function of the old dumpdir(8) program.  See also the
              -X option below.

       -x     The  named files are read from the given media. If a named file matches a directory
              whose contents are on the backup and the -h flag is not specified, the directory is
              recursively  extracted.  The  owner,  modification  time, and mode are restored (if
              possible). If no file argument is given, the root  directory  is  extracted,  which
              results in the entire content of the backup being extracted, unless the -h flag has
              been specified.  See also the -X option below.


       The following additional options may be specified:

       -a     In -i or -x mode, restore does ask the user for the  volume  number  on  which  the
              files  to be extracted are supposed to be (in order to minimise the time by reading
              only the interesting volumes). The -a option disables this behaviour and reads  all
              the  volumes starting with 1. This option is useful when the operator does not know
              on which volume the files to be extracted are and/or when  he  prefers  the  longer
              unattended mode rather than the shorter interactive mode.

       -A archive_file
              Read  the table of contents from archive_file instead of the media. This option can
              be used in combination with the -t, -i, or -x options, making it possible to  check
              whether files are on the media without having to mount the media.

       -b blocksize
              The number of kilobytes per dump record. If the -b option is not specified, restore
              tries to determine the media block size dynamically.

       -c     Normally, restore will try to determine dynamically whether the dump was made  from
              an  old  (pre-4.4)  or new format file system. The -c flag disables this check, and
              only allows reading a dump in the old format.

       -d     The -d (debug) flag causes restore to print debug information.

       -D filesystem
              The -D flag allows the user to specify the filesystem name when using restore  with
              the -C option to check the backup.

       -f file
              Read  the backup from file; file may be a special device file like /dev/st0 (a tape
              drive), /dev/sda1 (a disk drive), an ordinary file, or - (the standard  input).  If
              the name of the file is of the form host:file or user@host:file, restore reads from
              the named file on the remote host using rmt(8).

       -F script
              Run script at the beginning of each tape. The device name and  the  current  volume
              number  are  passed on the command line. The script must return 0 if restore should
              continue without asking the user to change the tape, 1 if restore  should  continue
              but  ask  the  user  to  change the tape. Any other exit code will cause restore to
              abort. For security reasons, restore reverts back to the real user ID and the  real
              group ID before running the script.

       -h     Extract  the  actual  directory,  rather  than  the  files that it references. This
              prevents hierarchical restoration of complete subtrees from the dump.

       -H hash_size
              Use a hashtable having the specified number of entries for storing the  directories
              entries  instead  of a linked list. This hashtable will considerably speed up inode
              lookups (visible especially in interactive mode when adding/removing files from the
              restore  list), but at the price of much more memory usage. The default value is 1,
              meaning no hashtable is used.

       -k     Use Kerberos authentication when contacting the remote tape server. (Only available
              if this options was enabled when restore was compiled.)

       -l     When  doing remote restores, assume the remote file is a regular file (instead of a
              tape device). If you're restoring a  remote  compressed  file,  you  will  need  to
              specify this option or restore will fail to access it correctly.

       -L limit
              The  -L  flag allows the user to specify a maximal number of miscompares when using
              restore with the -C option to check the backup. If this limit is  reached,  restore
              will  abort  with  an  error message. A value of 0 (the default value) disables the

       -m     Extract by inode numbers rather than by file name. This is useful  if  only  a  few
              files  are  being  extracted,  and  one  wants  to  avoid regenerating the complete
              pathname to the file.

       -M     Enables the multi-volume feature (for reading dumps made using  the  -M  option  of
              dump).  The name specified with -f is treated as a prefix and restore tries to read
              in sequence from <prefix>001, <prefix>002 etc.

       -N     The -N flag causes restore to perform a full execution as requested by one  of  -i,
              -R, -r, t or x command without actually writing any file on disk.

       -o     The  -o  flag  causes  restore  to  automatically  restore  the  current  directory
              permissions without asking the operator whether to do so in one of -i or -x modes.

       -Q file
              Use the file file in order to read tape position as stored  using  the  dump  Quick
              File Access mode, in one of -i, -x or -t mode.

              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 restoring from local or remote tapes  (see  above)  or
              from local or remote files.

       -s fileno
              Read from the specified fileno on a multi-file tape. File numbering starts at 1.

       -T directory
              The  -T  flag  allows  the  user  to  specify a directory to use for the storage of
              temporary files. The default  value  is  /tmp.   This  flag  is  most  useful  when
              restoring  files  after  having  booted  from a floppy. There might be little or no
              space on the floppy filesystem, but another source of space might exist.

       -u     When creating certain types of files, restore may generate a warning diagnostic  if
              they  already  exist in the target directory. To prevent this, the -u (unlink) flag
              causes restore to remove old entries before attempting to create new ones.

       -v     Normally restore does its work silently. The -v (verbose) flag causes  it  to  type
              the name of each file it treats preceded by its file type.

       -V     Enables reading multi-volume non-tape mediums like CDROMs.

       -X filelist
              Read  list  of  files  to  be  listed  or  extracted from the text file filelist in
              addition to those specified on the command line. This can be  used  in  conjunction
              with  the  -t or -x commands. The file filelist should contain file names separated
              by newlines.  filelist may be an ordinary file or - (the standard input).

       -y     Do not ask the user whether to abort the restore in the event of an error.   Always
              try to skip over the bad block(s) and continue.

       (The  4.3BSD option syntax is implemented for backward compatibility but is not documented


       Complains if it gets a read error. If y has  been  specified,  or  the  user  responds  y,
       restore will attempt to continue the restore.

       If a backup was made using more than one tape volume, restore will notify the user when it
       is time to mount the next volume. If the -x or -i flag has been  specified,  restore  will
       also  ask which volume the user wishes to mount. The fastest way to extract a few files is
       to start with the last volume, and work towards the first volume.

       There are numerous consistency checks that can be listed  by  restore.   Most  checks  are
       self-explanatory or can “never happen”. Common errors are given below:

       Converting to new file system format
              A  dump  tape created from the old file system has been loaded. It is automatically
              converted to the new file system format.

       <filename>: not found on tape
              The specified file name was listed in the tape directory, but was not found on  the
              tape. This is caused by tape read errors while looking for the file, and from using
              a dump tape created on an active file system.

       expected next file <inumber>, got <inumber>
              A file that was not listed in the directory showed up. This can occur when using  a
              dump created on an active file system.

       Incremental dump too low
              When  doing  an  incremental  restore,  a dump that was written before the previous
              incremental dump, or that has too low an incremental level has been loaded.

       Incremental dump too high
              When doing an incremental restore, a dump that does not begin  its  coverage  where
              the  previous  incremental dump left off, or that has too high an incremental level
              has been loaded.

       Tape read error while restoring <filename>

       Tape read error while skipping over inode <inumber>

       Tape read error while trying to resynchronize
              A tape (or other media) read error has occurred. If a file name is  specified,  its
              contents  are probably partially wrong. If an inode is being skipped or the tape is
              trying to resynchronize, no extracted files have been corrupted, though  files  may
              not be found on the tape.

       resync restore, skipped <num> blocks
              After  a  dump  read  error, restore may have to resynchronize itself. This message
              lists the number of blocks that were skipped over.


       Restore exits with zero status on success. Tape errors are indicated with an exit code  of

       When  doing a comparison of files from a dump, an exit code of 2 indicates that some files
       were modified or deleted since the dump was made.


       If the following environment variable exists it will be utilized by restore:

       TAPE   If no -f option was specified, restore will use the device specified  via  TAPE  as
              the   dump   device.    TAPE   may  be  of  the  form  tapename,  host:tapename  or

       TMPDIR The directory given in TMPDIR will be used  instead  of  /tmp  to  store  temporary

       RMT    The  environment  variable RMT will be used to determine the pathname of the remote
              rmt(8) program.

       RSH    Restore uses the contents of this variable to determine  the  name  of  the  remote
              shell command to use when doing a network restore (rsh, ssh etc.). If this variable
              is not set, rcmd(3) will be used, but only root  will  be  able  to  do  a  network


              the default tape drive

              file containing directories on the tape

              owner, mode, and time stamps for directories

              information passed between incremental restores


       dump(8), mount(8), mke2fs(8), rmt(8)


       Restore  can  get  confused  when  doing incremental restores from dumps that were made on
       active file systems.

       A level 0 dump must be done after a full restore. Because restore runs in  user  code,  it
       has  no  control  over inode allocation; thus a full dump must be done to get a new set of
       directories reflecting the new inode numbering, even though the content of  the  files  is

       The  temporary files /tmp/rstdir* and /tmp/rstmode* are generated with a unique name based
       on the date of the dump and the process ID (see mktemp(3)), except when -r or -R is  used.
       Because  -R  allows  you  to  restart  a  -r operation that may have been interrupted, the
       temporary files should be the same across different processes. In  all  other  cases,  the
       files  are  unique  because it is possible to have two different dumps started at the same
       time, and separate operations shouldn't conflict with each other.

       To do a network restore, you have to run restore as root or use a remote shell replacement
       (see  RSH variable).  This is due to the previous security history of dump and restore.  (
       restore is written to be setuid root, but we are not certain all bugs are  gone  from  the
       code - run setuid at your own risk.)

       At  the  end  of restores in -i or -x modes (unless -o option is in use), restore will ask
       the operator whether to set the permissions on the  current  directory.  If  the  operator
       confirms  this  action,  the  permissions on the directory from where restore was launched
       will be replaced by the permissions on the dumped root inode. Although this  behaviour  is
       not  really  a  bug,  it  has  proven  itself  to  be  confusing  for many users, so it is
       recommended to answer 'no', unless you're performing a full restore and  you  do  want  to
       restore the permissions on '/'.

       It  should be underlined that because it runs in user code, restore , when run with the -C
       option, sees the files as the kernel presents them, whereas dump sees all the files  on  a
       given  filesystem.  In  particular,  this can cause some confusion when comparing a dumped
       filesystem a part of which is hidden by a filesystem mounted on top of it.


       The dump/restore backup suite was ported to Linux's Second Extended File  System  by  Remy
       Card  <card@Linux.EU.Org>.  He  maintained  the initial versions of dump (up and including
       0.4b4, released in January 1997).

       Starting with 0.4b5, the new maintainer is Stelian Pop <>.


       The dump/restore backup suite is available from <>


       The restore command appeared in 4.2BSD.