1RESTORE(8) System management commands RESTORE(8)
2
6 restore - restore files or file systems from backups made with dump
7
9 restore -C [-cdHklMvVy] [-b blocksize] [-D filesystem] [-f file] [-F
10 script] [-L limit] [-s fileno] [-T directory]
11 restore -i [-acdhHklmMNouvVy] [-A file] [-b blocksize] [-f file] [-F
13 script] [-Q file] [-s fileno] [-T directory]
14 restore -P file [-acdhHklmMNuvVy] [-b blocksize] [-f file] [-F script]
16 [-s fileno] [-T directory] [-X filelist] [ file ... ]
17 restore -R [-cdHklMNuvVy] [-b blocksize] [-f file] [-F script] [-s
19 fileno] [-T directory]
20 restore -r [-cdHklMNuvVy] [-b blocksize] [-f file] [-F script] [-s
22 fileno] [-T directory]
23 restore -t [-cdhHklMNuvVy] [-A file] [-b blocksize] [-f file] [-F
25 script] [-Q file] [-s fileno] [-T directory] [-X filelist] [ file ... ]
26 restore -x [-adchHklmMNouvVy] [-A file] [-b blocksize] [-f file] [-F
28 script] [-Q file] [-s fileno] [-T directory] [-X filelist] [ file ... ]
29
31 The restore command performs the inverse function of dump(8). A full
32 backup of a file system may be restored and subsequent incremental
33 backups layered on top of it. Single files and directory subtrees may
34 be restored from full or partial backups. Restore works across a net‐
35 work; to do this see the -f flag described below. Other arguments to
36 the command are file or directory names specifying the files that are
37 to be restored. Unless the -h flag is specified (see below), the
38 appearance of a directory name refers to the files and (recursively)
39 subdirectories of that directory.
40 Exactly one of the following flags is required:
42 -C This mode allows comparison of files from a dump. Restore reads
44 the backup and compares its contents with files present on the
45 disk. It first changes its working directory to the root of the
46 filesystem that was dumped and compares the tape with the files
47 in its new current directory. See also the -L flag described
48 below.
49 -i This mode allows interactive restoration of files from a dump.
51 After reading in the directory information from the dump,
52 restore provides a shell like interface that allows the user to
53 move around the directory tree selecting files to be extracted.
54 The available commands are given below; for those commands that
55 require an argument, the default is the current directory.
56 add [arg]
58 The current directory or specified argument is added to
59 the list of files to be extracted. If a directory is
60 specified, then it and all its descendants are added to
61 the extraction list (unless the -h flag is specified on
62 the command line). Files that are on the extraction list
63 are prepended with a “*” when they are listed by ls.
64 cd arg Change the current working directory to the specified
66 argument.
67 delete [arg]
69 The current directory or specified argument is deleted
70 from the list of files to be extracted. If a directory is
71 specified, then it and all its descendants are deleted
72 from the extraction list (unless the -h flag is specified
73 on the command line). The most expedient way to extract
74 most of the files from a directory is to add the direc‐
75 tory to the extraction list and then delete those files
76 that are not needed.
77 extract
79 All files on the extraction list are extracted from the
80 dump. Restore will ask which volume the user wishes to
81 mount. The fastest way to extract a few files is to start
82 with the last volume and work towards the first volume.
83 help List a summary of the available commands.
85 ls [arg]
87 List the current or specified directory. Entries that are
88 directories are appended with a “/”. Entries that have
89 been marked for extraction are prepended with a “*”. If
90 the verbose flag is set, the inode number of each entry
91 is also listed.
92 pwd Print the full pathname of the current working directory.
94 quit Restore immediately exits, even if the extraction list is
96 not empty.
97 setmodes
99 All directories that have been added to the extraction
100 list have their owner, modes, and times set; nothing is
101 extracted from the dump. This is useful for cleaning up
102 after a restore has been prematurely aborted.
103 verbose
105 The sense of the -v flag is toggled. When set, the ver‐
106 bose flag causes the ls command to list the inode numbers
107 of all entries. It also causes restore to print out
108 information about each file as it is extracted.
109 -P file
111 Restore creates a new Quick File Access file file from an exist‐
112 ing dump file without restoring its contents.
113 -R Restore requests a particular tape of a multi-volume set on
115 which to restart a full restore (see the -r flag below). This is
116 useful if the restore has been interrupted.
117 -r Restore (rebuild) a file system. The target file system should
119 be made pristine with mke2fs(8), mounted, and the user cd'd into
120 the pristine file system before starting the restoration of the
121 initial level 0 backup. If the level 0 restores successfully,
122 the -r flag may be used to restore any necessary incremental
123 backups on top of the level 0. The -r flag precludes an interac‐
124 tive file extraction and can be detrimental to one's health (not
125 to mention the disk) if not used carefully. An example:
126 mke2fs /dev/sda1
128 mount /dev/sda1 /mnt
130 cd /mnt
132 restore rf /dev/st0
134 Note that restore leaves a file restoresymtable in the root
136 directory to pass information between incremental restore
137 passes. This file should be removed when the last incremental
138 has been restored.
139 Restore, in conjunction with mke2fs(8) and dump(8), may be used
141 to modify file system parameters such as size or block size.
142 -t The names of the specified files are listed if they occur on the
144 backup. If no file argument is given, the root directory is
145 listed, which results in the entire content of the backup being
146 listed, unless the -h flag has been specified. Note that the -t
147 flag replaces the function of the old dumpdir(8) program. See
148 also the -X option below.
149 -x The named files are read from the given media. If a named file
151 matches a directory whose contents are on the backup and the -h
152 flag is not specified, the directory is recursively extracted.
153 The owner, modification time, and mode are restored (if possi‐
154 ble). If no file argument is given, the root directory is
155 extracted, which results in the entire content of the backup
156 being extracted, unless the -h flag has been specified. See
157 also the -X option below.
158
160 The following additional options may be specified:
161 -a In -i or -x mode, restore does ask the user for the volume num‐
163 ber on which the files to be extracted are supposed to be (in
164 order to minimise the time by reading only the interesting vol‐
165 umes). The -a option disables this behaviour and reads all the
166 volumes starting with 1. This option is useful when the operator
167 does not know on which volume the files to be extracted are
168 and/or when he prefers the longer unattended mode rather than
169 the shorter interactive mode.
170 -A archive_file
172 Read the table of contents from archive_file instead of the
173 media. This option can be used in combination with the -t, -i,
174 or -x options, making it possible to check whether files are on
175 the media without having to mount the media.
176 -b blocksize
178 The number of kilobytes per dump record. If the -b option is not
179 specified, restore tries to determine the media block size
180 dynamically.
181 -c Normally, restore will try to determine dynamically whether the
183 dump was made from an old (pre-4.4) or new format file system.
184 The -c flag disables this check, and only allows reading a dump
185 in the old format.
186 -d The -d (debug) flag causes restore to print debug information.
188 -D filesystem
190 The -D flag allows the user to specify the filesystem name when
191 using restore with the -C option to check the backup.
192 -f file
194 Read the backup from file; file may be a special device file
195 like /dev/st0 (a tape drive), /dev/sda1 (a disk drive), an ordi‐
196 nary file, or - (the standard input). If the name of the file is
197 of the form host:file or user@host:file, restore reads from the
198 named file on the remote host using rmt(8).
199 -F script
201 Run script at the beginning of each tape. The device name and
202 the current volume number are passed on the command line. The
203 script must return 0 if restore should continue without asking
204 the user to change the tape, 1 if restore should continue but
205 ask the user to change the tape. Any other exit code will cause
206 restore to abort. For security reasons, restore reverts back to
207 the real user ID and the real group ID before running the
208 script.
209 -h Extract the actual directory, rather than the files that it ref‐
211 erences. This prevents hierarchical restoration of complete sub‐
212 trees from the dump.
213 -H hash_size
215 Use a hashtable having the specified number of entries for stor‐
216 ing the directories entries instead of a linked list. This
217 hashtable will considerably speed up inode lookups (visible
218 especially in interactive mode when adding/removing files from
219 the restore list), but at the price of much more memory usage.
220 The default value is 1, meaning no hashtable is used.
221 -k Use Kerberos authentication when contacting the remote tape
223 server. (Only available if this options was enabled when restore
224 was compiled.)
225 -l When doing remote restores, assume the remote file is a regular
227 file (instead of a tape device). If you're restoring a remote
228 compressed file, you will need to specify this option or restore
229 will fail to access it correctly.
230 -L limit
232 The -L flag allows the user to specify a maximal number of mis‐
233 compares when using restore with the -C option to check the
234 backup. If this limit is reached, restore will abort with an
235 error message. A value of 0 (the default value) disables the
236 check.
237 -m Extract by inode numbers rather than by file name. This is use‐
239 ful if only a few files are being extracted, and one wants to
240 avoid regenerating the complete pathname to the file.
241 -M Enables the multi-volume feature (for reading dumps made using
243 the -M option of dump). The name specified with -f is treated as
244 a prefix and restore tries to read in sequence from <prefix>001,
245 <prefix>002 etc.
246 -N The -N flag causes restore to perform a full execution as
248 requested by one of -i, -R, -r, t or x command without actually
249 writing any file on disk.
250 -o The -o flag causes restore to automatically restore the current
252 directory permissions without asking the operator whether to do
253 so in one of -i or -x modes.
254 -Q file
256 Use the file file in order to read tape position as stored using
257 the dump Quick File Access mode, in one of -i, -x or -t mode.
258 It is recommended to set up the st driver to return logical tape
260 positions rather than physical before calling dump/restore with
261 parameter -Q. Since not all tape devices support physical tape
262 positions those tape devices return an error during dump/restore
263 when the st driver is set to the default physical setting.
264 Please see the st(4) man page, option MTSETDRVBUFFER , or the
265 mt(1) man page, on how to set the driver to return logical tape
266 positions.
267 Before calling restore with parameter -Q, always make sure the
269 st driver is set to return the same type of tape position used
270 during the call to dump. Otherwise restore may be confused.
271 This option can be used when restoring from local or remote
273 tapes (see above) or from local or remote files.
274 -s fileno
276 Read from the specified fileno on a multi-file tape. File num‐
277 bering starts at 1.
278 -T directory
280 The -T flag allows the user to specify a directory to use for
281 the storage of temporary files. The default value is /tmp. This
282 flag is most useful when restoring files after having booted
283 from a floppy. There might be little or no space on the floppy
284 filesystem, but another source of space might exist.
285 -u When creating certain types of files, restore may generate a
287 warning diagnostic if they already exist in the target direc‐
288 tory. To prevent this, the -u (unlink) flag causes restore to
289 remove old entries before attempting to create new ones.
290 -v Normally restore does its work silently. The -v (verbose) flag
292 causes it to type the name of each file it treats preceded by
293 its file type.
294 -V Enables reading multi-volume non-tape mediums like CDROMs.
296 -X filelist
298 Read list of files to be listed or extracted from the text file
299 filelist in addition to those specified on the command line.
300 This can be used in conjunction with the -t or -x commands. The
301 file filelist should contain file names separated by newlines.
302 filelist may be an ordinary file or - (the standard input).
303 -y Do not ask the user whether to abort the restore in the event of
305 an error. Always try to skip over the bad block(s) and con‐
306 tinue.
307 (The 4.3BSD option syntax is implemented for backward compatibility but
309 is not documented here.)
310
312 Complains if it gets a read error. If y has been specified, or the user
313 responds y, restore will attempt to continue the restore.
314 If a backup was made using more than one tape volume, restore will
316 notify the user when it is time to mount the next volume. If the -x or
317 -i flag has been specified, restore will also ask which volume the user
318 wishes to mount. The fastest way to extract a few files is to start
319 with the last volume, and work towards the first volume.
320 There are numerous consistency checks that can be listed by restore.
322 Most checks are self-explanatory or can “never happen”. Common errors
323 are given below:
324 Converting to new file system format
326 A dump tape created from the old file system has been loaded. It
327 is automatically converted to the new file system format.
328 <filename>: not found on tape
330 The specified file name was listed in the tape directory, but
331 was not found on the tape. This is caused by tape read errors
332 while looking for the file, and from using a dump tape created
333 on an active file system.
334 expected next file <inumber>, got <inumber>
336 A file that was not listed in the directory showed up. This can
337 occur when using a dump created on an active file system.
338 Incremental dump too low
340 When doing an incremental restore, a dump that was written
341 before the previous incremental dump, or that has too low an
342 incremental level has been loaded.
343 Incremental dump too high
345 When doing an incremental restore, a dump that does not begin
346 its coverage where the previous incremental dump left off, or
347 that has too high an incremental level has been loaded.
348 Tape read error while restoring <filename>
350 Tape read error while skipping over inode <inumber>
352 Tape read error while trying to resynchronize
354 A tape (or other media) read error has occurred. If a file name
355 is specified, its contents are probably partially wrong. If an
356 inode is being skipped or the tape is trying to resynchronize,
357 no extracted files have been corrupted, though files may not be
358 found on the tape.
359 resync restore, skipped <num> blocks
361 After a dump read error, restore may have to resynchronize
362 itself. This message lists the number of blocks that were
363 skipped over.
364
366 Restore exits with zero status on success. Tape errors are indicated
367 with an exit code of 1.
368 When doing a comparison of files from a dump, an exit code of 2 indi‐
370 cates that some files were modified or deleted since the dump was made.
371
373 If the following environment variable exists it will be utilized by
374 restore:
375 TAPE If no -f option was specified, restore will use the device spec‐
377 ified via TAPE as the dump device. TAPE may be of the form
378 tapename, host:tapename or user@host:tapename.
379 TMPDIR The directory given in TMPDIR will be used instead of /tmp to
381 store temporary files.
382 RMT The environment variable RMT will be used to determine the path‐
384 name of the remote rmt(8) program.
385 RSH Restore uses the contents of this variable to determine the name
387 of the remote shell command to use when doing a network restore
388 (rsh, ssh etc.). If this variable is not set, rcmd(3) will be
389 used, but only root will be able to do a network restore.
390
392 /dev/st0
393 the default tape drive
394 /tmp/rstdir*
396 file containing directories on the tape
397 /tmp/rstmode*
399 owner, mode, and time stamps for directories
400 ./restoresymtable
402 information passed between incremental restores
403
405 dump(8), mount(8), mke2fs(8), rmt(8)
406
408 Restore can get confused when doing incremental restores from dumps
409 that were made on active file systems.
410 A level 0 dump must be done after a full restore. Because restore runs
412 in user code, it has no control over inode allocation; thus a full dump
413 must be done to get a new set of directories reflecting the new inode
414 numbering, even though the content of the files is unchanged.
415 The temporary files /tmp/rstdir* and /tmp/rstmode* are generated with a
417 unique name based on the date of the dump and the process ID (see
418 mktemp(3)), except when -r or -R is used. Because -R allows you to
419 restart a -r operation that may have been interrupted, the temporary
420 files should be the same across different processes. In all other
421 cases, the files are unique because it is possible to have two differ‐
422 ent dumps started at the same time, and separate operations shouldn't
423 conflict with each other.
424 To do a network restore, you have to run restore as root or use a
426 remote shell replacement (see RSH variable). This is due to the previ‐
427 ous security history of dump and restore. ( restore is written to be
428 setuid root, but we are not certain all bugs are gone from the code -
429 run setuid at your own risk.)
430 At the end of restores in -i or -x modes (unless -o option is in use),
432 restore will ask the operator whether to set the permissions on the
433 current directory. If the operator confirms this action, the permis‐
434 sions on the directory from where restore was launched will be replaced
435 by the permissions on the dumped root inode. Although this behaviour is
436 not really a bug, it has proven itself to be confusing for many users,
437 so it is recommended to answer 'no', unless you're performing a full
438 restore and you do want to restore the permissions on '/'.
439 It should be underlined that because it runs in user code, restore ,
441 when run with the -C option, sees the files as the kernel presents
442 them, whereas dump sees all the files on a given filesystem. In partic‐
443 ular, this can cause some confusion when comparing a dumped filesystem
444 a part of which is hidden by a filesystem mounted on top of it.
445
447 The dump/restore backup suite was ported to Linux's Second Extended
448 File System by Remy Card <card@Linux.EU.Org>. He maintained the initial
449 versions of dump (up and including 0.4b4, released in January 1997).
450 Starting with 0.4b5, the new maintainer is Stelian Pop
452 <stelian@popies.net>.
453
455 The dump/restore backup suite is available from <https://dump.source‐
456 forge.io>
457
459 The restore command appeared in 4.2BSD.
460BSD version 0.4b47 of 1 Jan 2021 RESTORE(8)