restore/restore.8.in

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  28 .\"     $Id: restore.8.in,v 1.33 2005/07/07 09:16:08 stelian Exp $
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  30 .TH RESTORE 8 "version __VERSION__ of __DATE__" BSD "System management commands"
  31 .SH NAME
  32 restore \- restore files or file systems from backups made with dump
  33 .SH SYNOPSIS
  34 .B restore \-C
  35 [\fB\-cdHklMvVy\fR]
  36 [\fB\-b \fIblocksize\fR]
  37 [\fB\-D \fIfilesystem\fR]
  38 [\fB\-f \fIfile\fR]
  39 [\fB\-F \fIscript\fR]
  40 [\fB\-L \fIlimit\fR]
  41 [\fB\-s \fIfileno\fR]
  42 [\fB\-T \fIdirectory\fR]
  43 .PP
  44 .B restore \-i
  45 [\fB\-acdhHklmMNouvVy\fR]
  46 [\fB\-A \fIfile\fR]
  47 [\fB\-b \fIblocksize\fR]
  48 [\fB\-f \fIfile\fR]
  49 [\fB\-F \fIscript\fR]
  50 [\fB\-Q \fIfile\fR]
  51 [\fB\-s \fIfileno\fR]
  52 [\fB\-T \fIdirectory\fR]
  53 .PP
  54 .B restore \-P
  55 .I file
  56 [\fB\-acdhHklmMNuvVy\fR]
  57 [\fB\-A \fIfile\fR]
  58 [\fB\-b \fIblocksize\fR]
  59 [\fB\-f \fIfile\fR]
  60 [\fB\-F \fIscript\fR]
  61 [\fB\-s \fIfileno\fR]
  62 [\fB\-T \fIdirectory\fR]
  63 [\fB\-X \fIfilelist\fR]
  64 [ \fIfile ... \fR]
  65 .PP
  66 .B restore \-R
  67 [\fB\-cdHklMNuvVy\fR]
  68 [\fB\-b \fIblocksize\fR]
  69 [\fB\-f \fIfile\fR]
  70 [\fB\-F \fIscript\fR]
  71 [\fB\-s \fIfileno\fR]
  72 [\fB\-T \fIdirectory\fR]
  73 .PP
  74 .B restore \-r
  75 [\fB\-cdHklMNuvVy\fR]
  76 [\fB\-b \fIblocksize\fR]
  77 [\fB\-f \fIfile\fR]
  78 [\fB\-F \fIscript\fR]
  79 [\fB\-s \fIfileno\fR]
  80 [\fB\-T \fIdirectory\fR]
  81 .PP
  82 .B restore \-t
  83 [\fB\-cdhHklMNuvVy\fR]
  84 [\fB\-A \fIfile\fR]
  85 [\fB\-b \fIblocksize\fR]
  86 [\fB\-f \fIfile\fR]
  87 [\fB\-F \fIscript\fR]
  88 [\fB\-Q \fIfile\fR]
  89 [\fB\-s \fIfileno\fR]
  90 [\fB\-T \fIdirectory\fR]
  91 [\fB\-X \fIfilelist\fR]
  92 [ \fIfile ... \fR]
  93 .PP
  94 .B restore \-x
  95 [\fB\-adchHklmMNouvVy\fR]
  96 [\fB\-A \fIfile\fR]
  97 [\fB\-b \fIblocksize\fR]
  98 [\fB\-f \fIfile\fR]
  99 [\fB\-F \fIscript\fR]
 100 [\fB\-Q \fIfile\fR]
 101 [\fB\-s \fIfileno\fR]
 102 [\fB\-T \fIdirectory\fR]
 103 [\fB\-X \fIfilelist\fR]
 104 [ \fIfile ... \fR]
 105 .SH DESCRIPTION
 106 The
 107 .B restore
 108 command performs the inverse function of
 109 .BR dump (8).
 110 A full backup of a file system may be restored and subsequent incremental
 111 backups layered on top of it. Single files and directory subtrees may be
 112 restored from full or partial backups.
 113 .B Restore
 114 works across a network; to do this see the
 115 .B \-f
 116 flag described below. Other arguments to the command are file or directory
 117 names specifying the files that are to be restored. Unless the
 118 .B \-h
 119 flag is specified (see below), the appearance of a directory name refers to
 120 the files and (recursively) subdirectories of that directory.
 121 .PP
 122 Exactly one of the following flags is required:
 123 .TP
 124 .B \-C
 125 This mode allows comparison of files from a dump.
 126 .B Restore
 127 reads the backup and compares its contents with files present on the disk. It
 128 first changes its working directory to the root of the filesystem that was
 129 dumped and compares the tape with the files in its new current directory. See
 130 also the
 131 .B \-L
 132 flag described below.
 133 .TP
 134 .B \-i
 135 This mode allows interactive restoration of files from a dump. After reading in
 136 the directory information from the dump,
 137 .B restore
 138 provides a shell like interface that allows the user to move around the
 139 directory tree selecting files to be extracted. The available commands are
 140 given below; for those commands that require an argument, the default is the
 141 current directory.
 142 .RS
 143 .TP
 144 .B add \fR[\fIarg\fR]
 145 The current directory or specified argument is added to the list of files to be
 146 extracted.  If a directory is specified, then it and all its descendents are
 147 added to the extraction list (unless the
 148 .B \-h
 149 flag is specified on the command line). Files that are on the extraction list
 150 are prepended with a \*(lq*\*(rq when they are listed by
 151 .BR ls .
 152 .TP
 153 .BI cd " arg"
 154 Change the current working directory to the specified argument.
 155 .TP
 156 .B delete \fR[\fIarg\fR]
 157 The current directory or specified argument is deleted from the list of files
 158 to be extracted. If a directory is specified, then it and all its descendents
 159 are deleted from the extraction list (unless the
 160 .B \-h
 161 flag is specified on the command line). The most expedient way to extract most
 162 of the files from a directory is to add the directory to the extraction list
 163 and then delete those files that are not needed.
 164 .TP
 165 .B extract
 166 All files on the extraction list are extracted from the dump.
 167 .B Restore
 168 will ask which volume the user wishes to mount. The fastest way to extract a f
 169 ew files is to start with the last volume and work towards the first volume.
 170 .TP
 171 .B help
 172 List a summary of the available commands.
 173 .TP
 174 .B ls \fR[\fIarg\fR]
 175 List the current or specified directory. Entries that are directories are
 176 appended with a \*(lq/\*(rq. Entries that have been marked for extraction are
 177 prepended with a \*(lq*\*(rq. If the verbose flag is set, the inode number of
 178 each entry is also listed.
 179 .TP
 180 .B pwd
 181 Print the full pathname of the current working directory.
 182 .TP
 183 .B quit
 184 .B Restore
 185 immediately exits, even if the extraction list is not empty.
 186 .TP
 187 .B setmodes
 188 All directories that have been added to the extraction list have their owner,
 189 modes, and times set; nothing is extracted from the dump. This is useful for
 190 cleaning up after a
 191 .B restore
 192 has been prematurely aborted.
 193 .TP
 194 .B verbose
 195 The sense of the
 196 .B \-v
 197 flag is toggled. When set, the verbose flag causes the
 198 .B ls
 199 command to list the inode numbers of all entries. It also causes
 200 .B restore
 201 to print out information about each file as it is extracted.
 202 .RE
 203 .TP
 204 .BI \-P " file"
 205 .B Restore
 206 creates a new Quick File Access file
 207 .I file
 208 from an existing dump file without restoring its contents.
 209 .TP
 210 .B \-R
 211 .B Restore
 212 requests a particular tape of a multi-volume set on which to restart a full
 213 restore (see the
 214 .B \-r
 215 flag below). This is useful if the restore has been interrupted.
 216 .TP
 217 .B \-r
 218 Restore (rebuild) a file system. The target file system should be made pristine
 219 with
 220 .BR mke2fs (8),
 221 mounted, and the user
 222 .BR cd 'd
 223 into the pristine file system before starting the restoration of the initial
 224 level 0 backup. If the level 0 restores successfully, the
 225 .B \-r
 226 flag may be used to restore any necessary incremental backups on top of the
 227 level 0. The
 228 .B \-r
 229 flag precludes an interactive file extraction and can be detrimental to one's
 230 health (not to mention the disk) if not used carefully. An example:
 231 .IP
 232 .RS 14
 233 .B mke2fs /dev/sda1
 234 .TP
 235 .B mount /dev/sda1 /mnt
 236 .TP
 237 .B cd /mnt
 238 .TP
 239 .B restore rf /dev/st0
 240 .RE
 241 .IP
 242 Note that
 243 .B restore
 244 leaves a file
 245 .I restoresymtable
 246 in the root directory to pass information between incremental restore passes.
 247 This file should be removed when the last incremental has been restored.
 248 .IP
 249 .BR Restore ,
 250 in conjunction with
 251 .BR mke2fs (8)
 252 and
 253 .BR dump (8),
 254 may be used to modify file system parameters such as size or block size.
 255 .TP
 256 .B \-t
 257 The names of the specified files are listed if they occur on the backup. If no
 258 file argument is given, the root directory is listed, which results in the
 259 entire content of the backup being listed, unless the
 260 .B \-h
 261 flag has been specified.  Note that the
 262 .B \-t
 263 flag replaces the function of the old
 264 .BR dumpdir (8)
 265 program.  See also the
 266 .B \-X
 267 option below.
 268 .TP
 269 .B \-x
 270 The named files are read from the given media. If a named file matches a
 271 directory whose contents are on the backup and the
 272 .B \-h
 273 flag is not specified, the directory is recursively extracted. The owner,
 274 modification time, and mode are restored (if possible). If no file argument is
 275 given, the root directory is extracted, which results in the entire content of
 276 the backup being extracted, unless the
 277 .B \-h
 278 flag has been specified.  See also the
 279 .B \-X
 280 option below.
 281 .SH OPTIONS
 282 The following additional options may be specified:
 283 .TP
 284 .B \-a
 285 In
 286 .B \-i
 287 or
 288 .B \-x
 289 mode,
 290 .B restore
 291 does ask the user for the volume number on which the files to be extracted are
 292 supposed to be (in order to minimise the time by reading only the interesting
 293 volumes). The
 294 .B \-a
 295 option disables this behaviour and reads all the volumes starting with 1. This
 296 option is useful when the operator does not know on which volume the files to
 297 be extracted are and/or when he prefers the longer unattended mode rather than
 298 the shorter interactive mode.
 299 .TP
 300 .BI \-A " archive_file"
 301 Read the table of contents from
 302 .I archive_file
 303 instead of the media. This option can be used in combination with the
 304 .BR \-t ,
 305 .BR \-i ,
 306 or
 307 .B \-x
 308 options, making it possible to check whether files are on the media without
 309 having to mount the media.
 310 .TP
 311 .BI \-b " blocksize"
 312 The number of kilobytes per dump record. If the
 313 .B \-b
 314 option is not specified,
 315 .B restore
 316 tries to determine the media block size dynamically.
 317 .TP
 318 .B \-c
 319 Normally,
 320 .B restore
 321 will try to determine dynamically whether the dump was made from an old
 322 (pre-4.4) or new format file system. The
 323 .B \-c
 324 flag disables this check, and only allows reading a dump in the old format.
 325 .TP
 326 .B \-d
 327 The
 328 .B \-d
 329 (debug) flag causes
 330 .B restore
 331 to print debug information.
 332 .TP
 333 .BI \-D " filesystem"
 334 The
 335 .B \-D
 336 flag allows the user to specify the filesystem name when using
 337 .B restore
 338 with the
 339 .B \-C
 340 option to check the backup.
 341 .TP
 342 .BI \-f " file"
 343 Read the backup from
 344 .IR file ;
 345 .I file
 346 may be a special device file like
 347 .I /dev/st0
 348 (a tape drive),
 349 .I /dev/sda1
 350 (a disk drive), an ordinary file, or
 351 .I \-
 352 (the standard input). If the name of the file is of the form
 353 .I host:file
 354 or
 355 .IR user@host:file ,
 356 .B restore
 357 reads from the named file on the remote host using
 358 .BR rmt (8).
 359 .TP
 360 .BI \-F " script"
 361 Run script at the beginning of each tape. The device name and the current
 362 volume number are passed on the command line. The script must return 0 if
 363 .B restore
 364 should continue without asking the user to change the tape, 1 if
 365 .B restore
 366 should continue but ask the user to change the tape. Any other exit code will
 367 cause
 368 .B restore
 369 to abort. For security reasons,
 370 .B restore
 371 reverts back to the real user ID and the real group ID before running the
 372 script.
 373 .TP
 374 .B \-h
 375 Extract the actual directory, rather than the files that it references. This
 376 prevents hierarchical restoration of complete subtrees from the dump.
 377 .TP
 378 .BI \-H " hash_size"
 379 Use a hashtable having the specified number of entries for storing the
 380 directories entries instead of a linked list. This hashtable will
 381 considerably speed up inode lookups (visible especialy in interactive
 382 mode when adding/removing files from the restore list), but at the
 383 price of much more memory usage. The default value is 1, meaning no
 384 hashtable is used.
 385 .TP
 386 .B \-k
 387 Use Kerberos authentication when contacting the remote tape server. (Only
 388 available if this options was enabled when
 389 .B restore
 390 was compiled.)
 391 .TP
 392 .B \-l
 393 When doing remote restores, assume the remote file is a regular file (instead
 394 of a tape device). If you're restoring a remote compressed file, you will need
 395 to specify this option or
 396 .B restore
 397 will fail to access it correctly.
 398 .TP
 399 .BI \-L " limit"
 400 The
 401 .B \-L
 402 flag allows the user to specify a maximal number of miscompares when using
 403 .B restore
 404 with the
 405 .B \-C
 406 option to check the backup. If this limit is reached,
 407 .B restore
 408 will abort with an error message. A value of 0 (the default value) disables
 409 the check.
 410 .TP
 411 .B \-m
 412 Extract by inode numbers rather than by file name. This is useful if only a few
 413 files are being extracted, and one wants to avoid regenerating the complete
 414 pathname to the file.
 415 .TP
 416 .B \-M
 417 Enables the multi-volume feature (for reading dumps made using the
 418 .B \-M
 419 option of dump). The name specified with
 420 .B \-f
 421 is treated as a prefix and
 422 .B restore
 423 tries to read in sequence from
 424 .I <prefix>001, <prefix>002
 425 etc.
 426 .TP
 427 .B \-N
 428 The
 429 .B \-N
 430 flag causes
 431 .B restore
 432 to perform a full execution as requested by one of
 433 .BR \-i ,
 434 .BR \-R ,
 435 .BR \-r ,
 436 .B t
 437 or
 438 .B x
 439 command without actually writing any file on disk.
 440 .TP
 441 .B \-o
 442 The
 443 .B \-o
 444 flag causes
 445 .B restore
 446 to automatically restore the current directory permissions without asking the
 447 operator whether to do so in one of
 448 .B \-i
 449 or
 450 .B \-x
 451 modes.
 452 .TP
 453 .BI \-Q " file"
 454 Use the file
 455 .I file
 456 in order to read tape position as stored using the dump Quick File Access mode,
 457 in one of
 458 .BR \-i ,
 459 .B \-x
 460 or
 461 .B \-t
 462 mode.
 463 .IP
 464 It is recommended to set up the st driver to return logical tape positions
 465 rather than physical before calling
 466 .B dump/restore
 467 with parameter
 468 .BR \-Q .
 469 Since not all tape devices support physical tape positions those tape devices
 470 return an error during
 471 .B dump/restore
 472 when the st driver is set to the default physical setting. Please see the
 473 .BR st (4)
 474 man page, option
 475 .B MTSETDRVBUFFER
 476 , or the
 477 .BR mt(1)
 478 man page, on how to set the driver to return logical tape positions.
 479 .IP
 480 Before calling
 481 .B restore
 482 with parameter
 483 .BR \-Q ,
 484 always make sure the st driver is set to return the same type of tape position
 485 used during the call to
 486 .BR dump .
 487 Otherwise
 488 .B restore
 489 may be confused.
 490 .IP
 491 This option can be used when restoring from local or remote tapes (see above)
 492 or from local or remote files.
 493 .TP
 494 .BI \-s " fileno"
 495 Read from the specified
 496 .I fileno
 497 on a multi-file tape. File numbering starts at 1.
 498 .TP
 499 .BI \-T " directory"
 500 The
 501 .B \-T
 502 flag allows the user to specify a directory to use for the storage of temporary
 503 files. The default value is
 504 .IR /tmp .
 505 This flag is most useful when restoring files after having booted from a
 506 floppy. There might be little or no space on the floppy filesystem, but another
 507 source of space might exist.
 508 .TP
 509 .B \-u
 510 When creating certain types of files,
 511 .B restore
 512 may generate a warning diagnostic if they already exist in the target
 513 directory. To prevent this, the
 514 .B \-u
 515 (unlink) flag causes
 516 .B restore
 517 to remove old entries before attempting to create new ones.
 518 .TP
 519 .B \-v
 520 Normally
 521 .B restore
 522 does its work silently. The
 523 .B \-v
 524 (verbose) flag causes it to type the name of each file it treats preceded by
 525 its file type.
 526 .TP
 527 .B \-V
 528 Enables reading multi-volume non-tape mediums like CDROMs.
 529 .TP
 530 .BI \-X " filelist"
 531 Read list of files to be listed or extracted from the text file
 532 .I filelist
 533 in addition to those specified on the command line. This can be used in
 534 conjunction with the
 535 .B \-t
 536 or
 537 .B \-x
 538 commands. The file
 539 .I filelist
 540 should contain file names separated by newlines.
 541 .I filelist
 542 may be an ordinary file or
 543 .I -
 544 (the standard input).
 545 .TP
 546 .B \-y
 547 Do not ask the user whether to abort the restore in the event of an error.
 548 Always try to skip over the bad block(s) and continue.
 549 .PP
 550 (The 4.3BSD option syntax is implemented for backward compatibility but is not
 551 documented here.)
 552 .SH DIAGNOSTICS
 553 Complains if it gets a read error. If
 554 .B y
 555 has been specified, or the user responds
 556 .BR y ,
 557 .B restore
 558 will attempt to continue the restore.
 559 .PP
 560 If a backup was made using more than one tape volume,
 561 .B restore
 562 will notify the user when it is time to mount the next volume. If the
 563 .B \-x
 564 or
 565 .B \-i
 566 flag has been specified,
 567 .B restore
 568 will also ask which volume the user wishes to mount. The fastest way to extract
 569 a few files is to start with the last volume, and work towards the first volume.
 570 .PP
 571 There are numerous consistency checks that can be listed by
 572 .BR restore .
 573 Most checks are self-explanatory or can \*(lqnever happen\*(rq. Common errors
 574 are given below:
 575 .TP
 576 .I Converting to new file system format
 577 A dump tape created from the old file system has been loaded. It is
 578 automatically converted to the new file system format.
 579 .TP
 580 .I <filename>: not found on tape
 581 The specified file name was listed in the tape directory, but was not found on
 582 the tape. This is caused by tape read errors while looking for the file, and
 583 from using a dump tape created on an active file system.
 584 .TP
 585 .I expected next file <inumber>, got <inumber>
 586 A file that was not listed in the directory showed up. This can occur when
 587 using a dump created on an active file system.
 588 .TP
 589 .I Incremental dump too low
 590 When doing an incremental restore, a dump that was written before the previous
 591 incremental dump, or that has too low an incremental level has been loaded.
 592 .TP
 593 .I Incremental dump too high
 594 When doing an incremental restore, a dump that does not begin its coverage
 595 where the previous incremental dump left off, or that has too high an
 596 incremental level has been loaded.
 597 .TP
 598 .I Tape read error while restoring <filename>
 599 .TP
 600 .I Tape read error while skipping over inode <inumber>
 601 .TP
 602 .I Tape read error while trying to resynchronize
 603 A tape (or other media) read error has occurred. If a file name is specified,
 604 its contents are probably partially wrong. If an inode is being skipped or the
 605 tape is trying to resynchronize, no extracted files have been corrupted, though
 606 files may not be found on the tape.
 607 .TP
 608 .I resync restore, skipped <num> blocks
 609 After a dump read error,
 610 .B restore
 611 may have to resynchronize itself. This message lists the number of blocks that
 612 were skipped over.
 613 .SH EXIT STATUS
 614 .B Restore
 615 exits with zero status on success. Tape errors are indicated with an exit code
 616 of 1.
 617 .PP
 618 When doing a comparison of files from a dump, an exit code of 2 indicates that
 619 some files were modified or deleted since the dump was made.
 620 .SH ENVIRONMENT
 621 If the following environment variable exists it will be utilized by
 622 .BR restore :
 623 .TP
 624 .B TAPE
 625 If no
 626 .B \-f
 627 option was specified,
 628 .B restore
 629 will use the device specified via
 630 .B TAPE
 631 as the dump device.
 632 .B TAPE
 633 may be of the form
 634 .IR tapename ,
 635 .I host:tapename
 636 or
 637 .IR user@host:tapename .
 638 .TP
 639 .B TMPDIR
 640 The directory given in
 641 .B TMPDIR
 642 will be used instead of
 643 .I /tmp
 644 to store temporary files.
 645 .TP
 646 .B RMT
 647 The environment variable
 648 .B RMT
 649 will be used to determine the pathname of the remote
 650 .BR rmt (8)
 651 program.
 652 .TP
 653 .B RSH
 654 .B Restore
 655 uses the contents of this variable to determine the name of the remote shell
 656 command to use when doing a network restore (rsh, ssh etc.). If this variable
 657 is not set,
 658 .BR rcmd (3)
 659 will be used, but only root will be able to do a network restore.
 660 .SH FILES
 661 .TP
 662 .I /dev/st0
 663 the default tape drive
 664 .TP
 665 .I /tmp/rstdir*
 666 file containing directories on the tape
 667 .TP
 668 .I /tmp/rstmode*
 669 owner, mode, and time stamps for directories
 670 .TP
 671 .I ./restoresymtable
 672 information passed between incremental restores
 673 .SH SEE ALSO
 674 .BR dump (8),
 675 .BR mount (8),
 676 .BR mke2fs (8),
 677 .BR rmt (8)
 678 .SH BUGS
 679 .B Restore
 680 can get confused when doing incremental restores from dumps that were made on
 681 active file systems.
 682 .PP
 683 A level 0 dump must be done after a full restore. Because
 684 .B restore
 685 runs in user code, it has no control over inode allocation; thus a full dump
 686 must be done to get a new set of directories reflecting the new inode
 687 numbering, even though the content of the files is unchanged.
 688 .PP
 689 The temporary files
 690 .I /tmp/rstdir*
 691 and
 692 .I /tmp/rstmode*
 693 are generated with a unique name based on the date of the dump and the process
 694 ID (see
 695 .BR mktemp (3) ),
 696 except when
 697 .B \-r
 698 or
 699 .B \-R
 700 is used. Because
 701 .B \-R
 702 allows you to restart a
 703 .B \-r
 704 operation that may have been interrupted, the temporary files should be the
 705 same across different processes. In all other cases, the files are unique
 706 because it is possible to have two different dumps started at the same time,
 707 and separate operations shouldn't conflict with each other.
 708 .PP
 709 To do a network restore, you have to run
 710 .B restore
 711 as root or use a remote shell replacement (see
 712 .B RSH
 713 variable).  This is due to the previous security history of
 714 .B dump
 715 and
 716 .BR restore .
 717 (
 718 .B restore
 719 is written to be setuid root, but we are not certain all bugs are gone from the
 720 code - run setuid at your own risk.)
 721 .PP
 722 At the end of restores in
 723 .B \-i
 724 or
 725 .B \-x
 726 modes (unless
 727 .B \-o
 728 option is in use),
 729 .B restore
 730 will ask the operator whether to set the permissions on the current
 731 directory. If the operator confirms this action, the permissions
 732 on the directory from where
 733 .B restore
 734 was launched will be replaced by the permissions on the dumped root
 735 inode. Although this behaviour is not really a bug, it has proven itself
 736 to be confusing for many users, so it is recommended to answer 'no',
 737 unless you're performing a full restore and you do want to restore the
 738 permissions on '/'.
 739 .PP
 740 It should be underlined that because it runs in user code,
 741 .B restore
 742 , when run with the
 743 .B \-C
 744 option, sees the files as the kernel presents them, whereas
 745 .B dump
 746 sees all the files on a given filesystem. In particular, this
 747 can cause some confusion when comparing a dumped filesystem a part
 748 of which is hidden by a filesystem mounted on top of it.
 749 .SH AUTHOR
 750 The
 751 .B dump/restore
 752 backup suite was ported to Linux's Second Extended File System by Remy Card
 753 <card@Linux.EU.Org>. He maintained the initial versions of
 754 .B dump
 755 (up and including 0.4b4, released in january 1997).
 756 .PP
 757 Starting with 0.4b5, the new maintainer is Stelian Pop <stelian@popies.net>.
 758 .SH AVAILABILITY
 759 The
 760 .B dump/restore
 761 backup suite is available from <http://dump.sourceforge.net>
 762 .SH HISTORY
 763 The
 764 .B restore
 765 command appeared in 4.2BSD.