1RDIFF-BACKUP(1) User Manuals RDIFF-BACKUP(1)
2
6 rdiff-backup - local/remote mirror and incremental backup
7
9 rdiff-backup [options] [[[user@]host1.foo]::source_directory]
10 [[[user@]host2.foo]::destination_directory]
11 rdiff-backup {{ -l | --list-increments } | --remove-older-than
13 time_interval | --list-at-time time | --list-changed-since time |
14 --list-increment-sizes | --verify | --verify-at-time time}
15 [[[user@]host2.foo]::destination_directory]
16 rdiff-backup --calculate-average statfile1 statfile2 ...
18 rdiff-backup --test-server [user1]@host1.net1::path
20 [[user2]@host2.net2::path] ...
21
24 rdiff-backup is a script, written in python(1) that backs up one direc‐
25 tory to another. The target directory ends up a copy (mirror) of the
26 source directory, but extra reverse diffs are stored in a special sub‐
27 directory of that target directory, so you can still recover files lost
28 some time ago. The idea is to combine the best features of a mirror
29 and an incremental backup. rdiff-backup also preserves symlinks, spe‐
30 cial files, hardlinks, permissions, uid/gid ownership, and modification
31 times.
32 rdiff-backup can also operate in a bandwidth efficient manner over a
34 pipe, like rsync(1). Thus you can use ssh and rdiff-backup to securely
35 back a hard drive up to a remote location, and only the differences
36 will be transmitted. Using the default settings, rdiff-backup requires
37 that the remote system accept ssh connections, and that rdiff-backup is
38 installed in the user's PATH on the remote system. For information on
39 other options, see the section on REMOTE OPERATION.
40 Note that you should not write to the mirror directory except with
42 rdiff-backup. Many of the increments are stored as reverse diffs, so
43 if you delete or modify a file, you may lose the ability to restore
44 previous versions of that file.
45 Finally, this man page is intended more as a precise description of the
47 behavior and syntax of rdiff-backup. New users may want to check out
48 the examples.html file included in the rdiff-backup distribution.
49
52 -b, --backup-mode
53 Force backup mode even if first argument appears to be an incre‐
54 ment or mirror file.
55 --calculate-average
57 Enter calculate average mode. The arguments should be a number
58 of statistics files. rdiff-backup will print the average of the
59 listed statistics files and exit.
60 --carbonfile
62 Enable backup of MacOS X carbonfile information.
63 --check-destination-dir
65 If an rdiff-backup session fails, running rdiff-backup with this
66 option on the destination dir will undo the failed directory.
67 This happens automatically if you attempt to back up to a direc‐
68 tory and the last backup failed.
69 --compare
71 This is equivalent to '--compare-at-time now'
72 --compare-at-time time
74 Compare a directory with the backup set at the given time. This
75 can be useful to see how archived data differs from current
76 data, or to check that a backup is current. This only compares
77 metadata, in the same way rdiff-backup decides whether a file
78 has changed.
79 --compare-full
81 This is equivalent to '--compare-full-at-time now'
82 --compare-full-at-time time
84 Compare a directory with the backup set at the given time. To
85 compare regular files, the repository data will be copied in its
86 entirety to the source side and compared byte by byte. This is
87 the slowest but most complete compare option.
88 --compare-hash
90 This is equivalent to '--compare-hash-at-time now'
91 --compare-hash-at-time time
93 Compare a directory with the backup set at the given time. Reg‐
94 ular files will be compared by computing their SHA1 digest on
95 the source side and comparing it to the digest recorded in the
96 metadata.
97 --create-full-path
99 Normally only the final directory of the destination path will
100 be created if it does not exist. With this option, all missing
101 directories on the destination path will be created. Use this
102 option with care: if there is a typo in the remote path, the
103 remote filesystem could fill up very quickly (by creating a
104 duplicate backup tree). For this reason this option is primarily
105 aimed at scripts which automate backups.
106 --current-time seconds
108 This option is useful mainly for testing. If set, rdiff-backup
109 will use it for the current time instead of consulting the
110 clock. The argument is the number of seconds since the epoch.
111 --exclude shell_pattern
113 Exclude the file or files matched by shell_pattern. If a direc‐
114 tory is matched, then files under that directory will also be
115 matched. See the FILE SELECTION section for more information.
116 --exclude-device-files
118 Exclude all device files. This can be useful for security/per‐
119 missions reasons or if rdiff-backup is not handling device files
120 correctly.
121 --exclude-fifos
123 Exclude all fifo files.
124 --exclude-filelist filename
126 Excludes the files listed in filename. If filename is handwrit‐
127 ten you probably want --exclude-globbing-filelist instead. See
128 the FILE SELECTION section for more information.
129 --exclude-filelist-stdin
131 Like --exclude-filelist, but the list of files will be read from
132 standard input. See the FILE SELECTION section for more infor‐
133 mation.
134 --exclude-globbing-filelist filename
136 Like --exclude-filelist but each line of the filelist will be
137 interpreted according to the same rules as --include and
138 --exclude.
139 --exclude-globbing-filelist-stdin
141 Like --exclude-globbing-filelist, but the list of files will be
142 read from standard input.
143 --exclude-other-filesystems
145 Exclude files on file systems (identified by device number)
146 other than the file system the root of the source directory is
147 on.
148 --exclude-regexp regexp
150 Exclude files matching the given regexp. Unlike the --exclude
151 option, this option does not match files in a directory it
152 matches. See the FILE SELECTION section for more information.
153 --exclude-special-files
155 Exclude all device files, fifo files, socket files, and symbolic
156 links.
157 --exclude-sockets
159 Exclude all socket files.
160 --exclude-symbolic-links
162 Exclude all symbolic links. This option is automatically enabled
163 if the backup source is running on native Windows to avoid back‐
164 ing-up NTFS reparse points.
165 --exclude-if-present filename
167 Exclude directories if filename is present. This option needs to
168 come before any other include or exclude options.
169 --force
171 Authorize a more drastic modification of a directory than usual
172 (for instance, when overwriting of a destination path, or when
173 removing multiple sessions with --remove-older-than). rdiff-
174 backup will generally tell you if it needs this. WARNING: You
175 can cause data loss if you mis-use this option. Furthermore, do
176 NOT use this option when doing a restore, as it will DELETE
177 FILES, unless you absolutely know what you are doing.
178 --group-mapping-file filename
180 Map group names and ids according the the group mapping file
181 filename. See the USERS AND GROUPS section for more informa‐
182 tion.
183 --include shell_pattern
185 Similar to --exclude but include matched files instead. Unlike
186 --exclude, this option will also match parent directories of
187 matched files (although not necessarily their contents). See
188 the FILE SELECTION section for more information.
189 --include-filelist filename
191 Like --exclude-filelist, but include the listed files instead.
192 If filename is handwritten you probably want --include-globbing-
193 filelist instead. See the FILE SELECTION section for more
194 information.
195 --include-filelist-stdin
197 Like --include-filelist, but read the list of included files
198 from standard input.
199 --include-globbing-filelist filename
201 Like --include-filelist but each line of the filelist will be
202 interpreted according to the same rules as --include and
203 --exclude.
204 --include-globbing-filelist-stdin
206 Like --include-globbing-filelist, but the list of files will be
207 read from standard input.
208 --include-regexp regexp
210 Include files matching the regular expression regexp. Only
211 files explicitly matched by regexp will be included by this
212 option. See the FILE SELECTION section for more information.
213 --include-special-files
215 Include all device files, fifo files, socket files, and symbolic
216 links.
217 --include-symbolic-links
219 Include all symbolic links.
220 --list-at-time time
222 List the files in the archive that were present at the given
223 time. If a directory in the archive is specified, list only the
224 files under that directory.
225 --list-changed-since time
227 List the files that have changed in the destination directory
228 since the given time. See TIME FORMATS for the format of time.
229 If a directory in the archive is specified, list only the files
230 under that directory. This option does not read the source
231 directory; it is used to compare the contents of two different
232 rdiff-backup sessions.
233 -l, --list-increments
235 List the number and date of partial incremental backups con‐
236 tained in the specified destination directory. No backup or
237 restore will take place if this option is given.
238 --list-increment-sizes
240 List the total size of all the increment and mirror files by
241 time. This may be helpful in deciding how many increments to
242 keep, and when to --remove-older-than. Specifying a subdirec‐
243 tory is allowable; then only the sizes of the mirror and incre‐
244 ments pertaining to that subdirectory will be listed.
245 --max-file-size size
247 Exclude files that are larger than the given size in bytes
248 --min-file-size size
250 Exclude files that are smaller than the given size in bytes
251 --never-drop-acls
253 Exit with error instead of dropping acls or acl entries. Nor‐
254 mally this may happen (with a warning) because the destination
255 does not support them or because the relevant user/group names
256 do not exist on the destination side.
257 --no-acls
259 No Access Control Lists - disable backup of ACLs
260 --no-carbonfile
262 Disable backup of MacOS X carbonfile information
263 --no-compare-inode
265 This option prevents rdiff-backup from flagging a hardlinked
266 file as changed when its device number and/or inode changes.
267 This option is useful in situations where the source filesystem
268 lacks persistent device and/or inode numbering. For example,
269 network filesystems may have mount-to-mount differences in their
270 device number (but possibly stable inode numbers); USB/1394
271 devices may come up at different device numbers each remount
272 (but would generally have same inode number); and there are
273 filesystems which don't even have the same inode numbers from
274 use to use. Without the option rdiff-backup may generate unnec‐
275 essary numbers of tiny diff files.
276 --no-compression
278 Disable the default gzip compression of most of the .snapshot
279 and .diff increment files stored in the rdiff-backup-data direc‐
280 tory. A backup volume can contain compressed and uncompressed
281 increments, so using this option inconsistently is fine.
282 --no-compression-regexp regexp
284 Do not compress increments based on files whose filenames match
285 regexp. The default includes many common audiovisual and ar‐
286 chive files, and may be found in Globals.py.
287 --no-eas
289 No Extended Attributes support - disable backup of EAs.
290 --no-file-statistics
292 This will disable writing to the file_statistics file in the
293 rdiff-backup-data directory. rdiff-backup will run slightly
294 quicker and take up a bit less space.
295 --no-hard-links
297 Don't replicate hard links on destination side. If many hard-
298 linked files are present, this option can drastically decrease
299 memory usage. This option is enabled by default if the backup
300 source or restore destination is running on native Windows.
301 --null-separator
303 Use nulls (\0) instead of newlines (\n) as line separators,
304 which may help when dealing with filenames containing newlines.
305 This affects the expected format of the files specified by the
306 --{include|exclude}-filelist[-stdin] switches as well as the
307 format of the directory statistics file.
308 --parsable-output
310 If set, rdiff-backup's output will be tailored for easy parsing
311 by computers, instead of convenience for humans. Currently this
312 only applies when listing increments using the -l or --list-
313 increments switches, where the time will be given in seconds
314 since the epoch.
315 --override-chars-to-quote
317 If the filesystem to which we are backing up is not case-sensi‐
318 tive, automatic 'quoting' of characters occurs. For example, a
319 file 'Developer.doc' will be converted into ';068eveloper.doc'.
320 To override this behavior, you need to specify this option.
321 --preserve-numerical-ids
323 If set, rdiff-backup will preserve uids/gids instead of trying
324 to preserve unames and gnames. See the USERS AND GROUPS section
325 for more information.
326 --print-statistics
328 If set, summary statistics will be printed after a successful
329 backup. If not set, this information will still be available
330 from the session statistics file. See the STATISTICS section
331 for more information.
332 -r, --restore-as-of restore_time
334 Restore the specified directory as it was as of restore_time.
335 See the TIME FORMATS section for more information on the format
336 of restore_time, and see the RESTORING section for more informa‐
337 tion on restoring.
338 --remote-cmd cmd
340 Deprecated. Please use --remote-schema instead
341 --remote-schema schema
343 Specify an alternate method of connecting to a remote computer.
344 This is necessary to get rdiff-backup not to use ssh for remote
345 backups, or if, for instance, rdiff-backup is not in the PATH on
346 the remote side. See the REMOTE OPERATION section for more
347 information.
348 --remote-tempdir path
350 Adds the --tempdir option with argument path when invoking
351 remote instances of rdiff-backup.
352 --remove-older-than time_spec
354 Remove the incremental backup information in the destination
355 directory that has been around longer than the given time.
356 time_spec can be either an absolute time, like "2002-01-04", or
357 a time interval. The time interval is an integer followed by
358 the character s, m, h, D, W, M, or Y, indicating seconds, min‐
359 utes, hours, days, weeks, months, or years respectively, or a
360 number of these concatenated. For example, 32m means 32 min‐
361 utes, and 3W2D10h7s means 3 weeks, 2 days, 10 hours, and 7 sec‐
362 onds. In this context, a month means 30 days, a year is 365
363 days, and a day is always 86400 seconds.
364 rdiff-backup cannot remove-older-than and back up or restore in
366 a single session. In order to both backup a directory and
367 remove old files in it, you must run rdiff-backup twice.
368 By default, rdiff-backup will only delete information from one
370 session at a time. To remove two or more sessions at the same
371 time, supply the --force option (rdiff-backup will tell you if
372 --force is required).
373 Note that snapshots of deleted files are covered by this opera‐
375 tion. Thus if you deleted a file two weeks ago, backed up imme‐
376 diately afterwards, and then ran rdiff-backup with --remove-
377 older-than 10D today, no trace of that file would remain.
378 Finally, file selection options such as --include and --exclude
379 don't affect --remove-older-than.
380 --restrict path
382 Require that all file access be inside the given path. This
383 switch, and the following two, are intended to be used with the
384 --server switch to provide a bit more protection when doing
385 automated remote backups. They are not intended as your only
386 line of defense so please don't do something silly like allow
387 public access to an rdiff-backup server run with --restrict-
388 read-only.
389 --restrict-read-only path
391 Like --restrict, but also reject all write requests.
392 --restrict-update-only path
394 Like --restrict, but only allow writes as part of an incremental
395 backup. Requests for other types of writes (for instance,
396 deleting path) will be rejected.
397 --server
399 Enter server mode (not to be invoked directly, but instead used
400 by another rdiff-backup process on a remote computer).
401 --ssh-no-compression
403 When running ssh, do not use the -C option to enable compres‐
404 sion. --ssh-no-compression is ignored if you specify a new
405 schema using --remote-schema.
406 --tempdir path
408 Sets the directory that rdiff-backup uses for temporary files to
409 the given path. The environment variables TMPDIR, TEMP, and TMP
410 can also be used to set the temporary files directory. See the
411 documentation of the Python tempfile module for more informa‐
412 tion.
413 --terminal-verbosity [0-9]
415 Select which messages will be displayed to the terminal. If
416 missing the level defaults to the verbosity level.
417 --test-server
419 Test for the presence of a compatible rdiff-backup server as
420 specified in the following host::filename argument(s). The
421 filename section will be ignored.
422 --user-mapping-file filename
424 Map user names and ids according to the user mapping file file‐
425 name. See the USERS AND GROUPS section for more information.
426 -v[0-9], --verbosity [0-9]
428 Specify verbosity level (0 is totally silent, 3 is the default,
429 and 9 is noisiest). This determines how much is written to the
430 log file.
431 --verify
433 This is short for --verify-at-time now
434 --verify-at-time now
436 Check all the data in the repository at the given time by com‐
437 puting the SHA1 hash of all the regular files and comparing them
438 with the hashes stored in the metadata file.
439 -V, --version
441 Print the current version and exit
442
445 There are two ways to tell rdiff-backup to restore a file or directory.
446 Firstly, you can run rdiff-backup on a mirror file and use the -r or
447 --restore-as-of options. Secondly, you can run it on an increment
448 file.
449 For example, suppose in the past you have run:
451 rdiff-backup /usr /usr.backup
453 to back up the /usr directory into the /usr.backup directory, and now
455 want a copy of the /usr/local directory the way it was 3 days ago
456 placed at /usr/local.old.
457 One way to do this is to run:
459 rdiff-backup -r 3D /usr.backup/local /usr/local.old
461 where above the "3D" means 3 days (for other ways to specify the time,
463 see the TIME FORMATS section). The /usr.backup/local directory was
464 selected, because that is the directory containing the current version
465 of /usr/local.
466 Note that the option to --restore-as-of always specifies an exact time.
468 (So "3D" refers to the instant 72 hours before the present.) If there
469 was no backup made at that time, rdiff-backup restores the state
470 recorded for the previous backup. For instance, in the above case, if
471 "3D" is used, and there are only backups from 2 days and 4 days ago,
472 /usr/local as it was 4 days ago will be restored.
473 The second way to restore files involves finding the corresponding
475 increment file. It would be in the /backup/rdiff-backup-data/incre‐
476 ments/usr directory, and its name would be something like
477 "local.2002-11-09T12:43:53-04:00.dir" where the time indicates it is
478 from 3 days ago. Note that the increment files all end in ".diff",
479 ".snapshot", ".dir", or ".missing", where ".missing" just means that
480 the file didn't exist at that time (finally, some of these may be gzip-
481 compressed, and have an extra ".gz" to indicate this). Then running:
482 rdiff-backup /backup/rdiff-backup-data/incre‐
484 ments/usr/local.<time>.dir /usr/local.old
485 would also restore the file as desired.
487 If you are not sure exactly which version of a file you need, it is
489 probably easiest to either restore from the increments files as
490 described immediately above, or to see which increments are available
491 with -l/--list-increments, and then specify exact times into
492 -r/--restore-as-of.
493
496 rdiff-backup uses time strings in two places. Firstly, all of the
497 increment files rdiff-backup creates will have the time in their file‐
498 names in the w3 datetime format as described in a w3 note at
499 http://www.w3.org/TR/NOTE-datetime. Basically they look like
500 "2001-07-15T04:09:38-07:00", which means what it looks like. The
501 "-07:00" section means the time zone is 7 hours behind UTC.
502 Secondly, the -r, --restore-as-of, and --remove-older-than options take
504 a time string, which can be given in any of several formats:
505 1. the string "now" (refers to the current time)
507 2. a sequences of digits, like "123456890" (indicating the time in
509 seconds after the epoch)
510 3. A string like "2002-01-25T07:00:00+02:00" in datetime format
512 4. An interval, which is a number followed by one of the characters
514 s, m, h, D, W, M, or Y (indicating seconds, minutes, hours,
515 days, weeks, months, or years respectively), or a series of such
516 pairs. In this case the string refers to the time that preceded
517 the current time by the length of the interval. For instance,
518 "1h78m" indicates the time that was one hour and 78 minutes ago.
519 The calendar here is unsophisticated: a month is always 30 days,
520 a year is always 365 days, and a day is always 86400 seconds.
521 5. A date format of the form YYYY/MM/DD, YYYY-MM-DD, MM/DD/YYYY, or
523 MM-DD-YYYY, which indicates midnight on the day in question,
524 relative to the current timezone settings. For instance,
525 "2002/3/5", "03-05-2002", and "2002-3-05" all mean March 5th,
526 2002.
527 6. A backup session specification which is a non-negative integer
529 followed by 'B'. For instance, '0B' specifies the time of the
530 current mirror, and '3B' specifies the time of the 3rd newest
531 increment.
532
535 In order to access remote files, rdiff-backup opens up a pipe to a copy
536 of rdiff-backup running on the remote machine. Thus rdiff-backup must
537 be installed on both ends. To open this pipe, rdiff-backup first
538 splits the filename into host_info::pathname. It then substitutes
539 host_info into the remote schema, and runs the resulting command, read‐
540 ing its input and output.
541 The default remote schema is 'ssh -C %s rdiff-backup --server' where
543 host_info is substituted for '%s'. So if the host_info is
544 user@host.net, then rdiff-backup runs 'ssh user@host.net rdiff-backup
545 --server'. Using --remote-schema, rdiff-backup can invoke an arbitrary
546 command in order to open up a remote pipe. For instance,
547 rdiff-backup --remote-schema 'cd /usr; %s' foo 'rdiff-backup
548 --server'::bar
549 is basically equivalent to (but slower than)
550 rdiff-backup foo /usr/bar
551 Concerning quoting, if for some reason you need to put two consecutive
553 colons in the host_info section of a host_info::pathname argument, or
554 in the pathname of a local file, you can quote one of them by prepend‐
555 ing a backslash. So in 'a\::b::c', host_info is 'a::b' and the path‐
556 name is 'c'. Similarly, if you want to refer to a local file whose
557 filename contains two consecutive colons, like 'strange::file', you'll
558 have to quote one of the colons as in 'strange\::file'. Because the
559 backslash is a quote character in these circumstances, it too must be
560 quoted to get a literal backslash, so 'foo\::\\bar' evaluates to
561 'foo::\bar'. To make things more complicated, because the backslash is
562 also a common shell quoting character, you may need to type in '\\\\'
563 at the shell prompt to get a literal backslash (if it makes you feel
564 better, I had to type in 8 backslashes to get that in this man
565 page...). And finally, to include a literal % in the string specified
566 by --remote-schema, quote it with another %, as in %%.
567 Although ssh itself may be secure, using rdiff-backup in the default
569 way presents some security risks. For instance if the server is run as
570 root, then an attacker who compromised the client could then use rdiff-
571 backup to overwrite arbitrary server files by "backing up" over them.
572 Such a setup can be made more secure by using the sshd configuration
573 option command="rdiff-backup --server" possibly along with the
574 --restrict* options to rdiff-backup. For more information, see the web
575 page, the wiki, and the entries for the --restrict* options on this man
576 page.
577
580 rdiff-backup has a number of file selection options. When rdiff-backup
581 is run, it searches through the given source directory and backs up all
582 the files matching the specified options. This selection system may
583 appear complicated, but it is supposed to be flexible and easy-to-use.
584 If you just want to learn the basics, first look at the selection exam‐
585 ples in the examples.html file included in the package, or on the web
586 at http://rdiff-backup.nongnu.org/examples.html
587 rdiff-backup's selection system was originally inspired by rsync(1),
589 but there are many differences. (For instance, trailing backslashes
590 have no special significance.)
591 The file selection system comprises a number of file selection condi‐
593 tions, which are set using one of the following command line options:
594 --exclude, --exclude-filelist, --exclude-device-files, --exclude-fifos,
595 --exclude-sockets, --exclude-symbolic-links, --exclude-globbing-
596 filelist, --exclude-globbing-filelist-stdin, --exclude-filelist-stdin,
597 --exclude-regexp, --exclude-special-files, --include, --include-
598 filelist, --include-globbing-filelist, --include-globbing-filelist-
599 stdin, --include-filelist-stdin, and --include-regexp. Each file
600 selection condition either matches or doesn't match a given file. A
601 given file is excluded by the file selection system exactly when the
602 first matching file selection condition specifies that the file be
603 excluded; otherwise the file is included. When backing up, if a file
604 is excluded, rdiff-backup acts as if that file does not exist in the
605 source directory. When restoring, an excluded file is considered not
606 to exist in either the source or target directories.
607 For instance,
609 rdiff-backup --include /usr --exclude /usr /usr /backup
611 is exactly the same as
613 rdiff-backup /usr /backup
615 because the include and exclude directives match exactly the same
617 files, and the --include comes first, giving it precedence. Similarly,
618 rdiff-backup --include /usr/local/bin --exclude /usr/local /usr
620 /backup
621 would backup the /usr/local/bin directory (and its contents), but not
623 /usr/local/doc.
624 The include, exclude, include-globbing-filelist, and exclude-globbing-
626 filelist options accept extended shell globbing patterns. These pat‐
627 terns can contain the special patterns *, **, ?, and [...]. As in a
628 normal shell, * can be expanded to any string of characters not con‐
629 taining "/", ? expands to any character except "/", and [...] expands
630 to a single character of those characters specified (ranges are accept‐
631 able). The new special pattern, **, expands to any string of charac‐
632 ters whether or not it contains "/". Furthermore, if the pattern
633 starts with "ignorecase:" (case insensitive), then this prefix will be
634 removed and any character in the string can be replaced with an upper-
635 or lowercase version of itself.
636 If you need to match filenames which contain the above globbing charac‐
638 ters, they may be escaped using a backslash "\". The backslash will
639 only escape the character following it so for ** you will need to use
640 "\*\*" to avoid escaping it to the * globbing character.
641 Remember that you may need to quote these characters when typing them
643 into a shell, so the shell does not interpret the globbing patterns
644 before rdiff-backup sees them.
645 The --exclude pattern option matches a file iff:
647 1. pattern can be expanded into the file's filename, or
649 2. the file is inside a directory matched by the option.
651 Conversely, --include pattern matches a file iff:
653 1. pattern can be expanded into the file's filename,
655 2. the file is inside a directory matched by the option, or
657 3. the file is a directory which contains a file matched by the
659 option.
660 For example,
662 --exclude /usr/local
664 matches /usr/local, /usr/local/lib, and /usr/local/lib/netscape. It is
666 the same as --exclude /usr/local --exclude '/usr/local/**'.
667 --include /usr/local
669 specifies that /usr, /usr/local, /usr/local/lib, and
671 /usr/local/lib/netscape (but not /usr/doc) all be backed up. Thus you
672 don't have to worry about including parent directories to make sure
673 that included subdirectories have somewhere to go. Finally,
674 --include ignorecase:'/usr/[a-z0-9]foo/*/**.py'
676 would match a file like /usR/5fOO/hello/there/world.py. If it did
678 match anything, it would also match /usr. If there is no existing file
679 that the given pattern can be expanded into, the option will not match
680 /usr.
681 The --include-filelist, --exclude-filelist, --include-filelist-stdin,
683 and --exclude-filelist-stdin options also introduce file selection con‐
684 ditions. They direct rdiff-backup to read in a file, each line of
685 which is a file specification, and to include or exclude the matching
686 files. Lines are separated by newlines or nulls, depending on whether
687 the --null-separator switch was given. Each line in a filelist is
688 interpreted similarly to the way extended shell patterns are, with a
689 few exceptions:
690 1. Globbing patterns like *, **, ?, and [...] are not expanded.
692 2. Include patterns do not match files in a directory that is
694 included. So /usr/local in an include file will not match
695 /usr/local/doc.
696 3. Lines starting with "+ " are interpreted as include directives,
698 even if found in a filelist referenced by --exclude-filelist.
699 Similarly, lines starting with "- " exclude files even if they
700 are found within an include filelist.
701 For example, if the file "list.txt" contains the lines:
703 /usr/local
705 - /usr/local/doc
706 /usr/local/bin
707 + /var
708 - /var
709 then "--include-filelist list.txt" would include /usr, /usr/local, and
711 /usr/local/bin. It would exclude /usr/local/doc,
712 /usr/local/doc/python, etc. It neither excludes nor includes
713 /usr/local/man, leaving the fate of this directory to the next specifi‐
714 cation condition. Finally, it is undefined what happens with /var. A
715 single file list should not contain conflicting file specifications.
716 The --include-globbing-filelist and --exclude-globbing-filelist options
718 also specify filelists, but each line in the filelist will be inter‐
719 preted as a globbing pattern the way --include and --exclude options
720 are interpreted (although "+ " and "- " prefixing is still allowed).
721 For instance, if the file "globbing-list.txt" contains the lines:
722 dir/foo
724 + dir/bar
725 - **
726 Then "--include-globbing-filelist globbing-list.txt" would be exactly
728 the same as specifying "--include dir/foo --include dir/bar --exclude
729 **" on the command line.
730 Finally, the --include-regexp and --exclude-regexp allow files to be
732 included and excluded if their filenames match a python regular expres‐
733 sion. Regular expression syntax is too complicated to explain here,
734 but is covered in Python's library reference. Unlike the --include and
735 --exclude options, the regular expression options don't match files
736 containing or contained in matched files. So for instance
737 --include '[0-9]{7}(?!foo)'
739 matches any files whose full pathnames contain 7 consecutive digits
741 which aren't followed by 'foo'. However, it wouldn't match /home even
742 if /home/ben/1234567 existed.
743
746 There can be complications preserving ownership across systems. For
747 instance the username that owns a file on the source system may not
748 exist on the destination. Here is how rdiff-backup maps ownership on
749 the source to the destination (or vice-versa, in the case of restor‐
750 ing):
751 1. If the --preserve-numerical-ids option is given, the remote
754 files will always have the same uid and gid, both for ownership
755 and ACL entries. This may cause unames and gnames to change.
756 2. Otherwise, attempt to preserve the user and group names for own‐
758 ership and in ACLs. This may result in files having different
759 uids and gids across systems.
760 3. If a name cannot be preserved (e.g. because the username does
762 not exist), preserve the original id, but only in cases of user
763 and group ownership. For ACLs, omit any entry that has a bad
764 user or group name.
765 4. The --user-mapping-file and --group-mapping-file options over‐
767 ride this behavior. If either of these options is given, the
768 policy described in 2 and 3 above will be followed, but with the
769 mapped user and group instead of the original. If you specify
770 both --preserve-numerical-ids and one of the mapping options,
771 the behavior is undefined.
772 The user and group mapping files both have the same form:
774 old_name_or_id1:new_name_or_id1
776 old_name_or_id2:new_name_or_id2
777 <etc>
778 Each line should contain a name or id, followed by a colon ":", fol‐
780 lowed by another name or id. If a name or id is not listed, they are
781 treated in the default way described above.
782 When restoring, the above behavior is also followed, but note that the
784 original source user/group information will be the input, not the
785 already mapped user/group information present in the backup repository.
786 For instance, suppose you have mapped all the files owned by alice in
787 the source so that they are owned by ben in the repository, and now you
788 want to restore, making sure the files owned originally by alice are
789 still owned by alice. In this case there is no need to use any of the
790 mapping options. However, if you wanted to restore the files so that
791 the files originally owned by alice on the source are now owned by ben,
792 you would have to use the mapping options, even though you just want
793 the unames of the repository's files preserved in the restored files.
794
798 Every session rdiff-backup saves various statistics into two files, the
799 session statistics file at rdiff-backup-data/session_statis‐
800 tics.<time>.data and the directory statistics file at rdiff-backup-
801 data/directory_statistics.<time>.data. They are both text files and
802 contain similar information: how many files changed, how many were
803 deleted, the total size of increment files created, etc. However, the
804 session statistics file is intended to be very readable and only
805 describes the session as a whole. The directory statistics file is
806 more compact (and slightly less readable) but describes every directory
807 backed up. It also may be compressed to save space.
808 Statistics-related options include --print-statistics and --null-sepa‐
810 rator.
811 Also, rdiff-backup will save various messages to the log file, which is
813 rdiff-backup-data/backup.log for backup sessions and rdiff-backup-
814 data/restore.log for restore sessions. Generally what is written to
815 this file will coincide with the messages displayed to stdout or
816 stderr, although this can be changed with the --terminal-verbosity
817 option.
818 The log file is not compressed and can become quite large if rdiff-
820 backup is run with high verbosity.
821
824 If rdiff-backup finishes successfully, the exit status will be 0. If
825 there is an unrecoverable (critical) error, it will be non-zero (usu‐
826 ally 1, but don't depend on this specific value). When setting up
827 rdiff-backup to run automatically (as from cron(8) or similar) it is
828 probably a good idea to check the exit code.
829
832 The gzip library in versions 2.2 and earlier of python (but fixed in
833 2.3a1) has trouble producing files over 2GB in length. This bug will
834 prevent rdiff-backup from producing large compressed increments (snap‐
835 shots or diffs). A workaround is to disable compression for large
836 uncompressable files.
837
840 Ben Escoto <ben@emerose.org>
841 Feel free to ask me questions or send me bug reports, but you may want
843 to see the web page, mentioned below, first.
844
847 python(1), rdiff(1), rsync(1), ssh(1). The main rdiff-backup web page
848 is at http://rdiff-backup.nongnu.org/. It has more information, links
849 to the mailing list and CVS, etc.
850Version 1.2.8 March 2009 RDIFF-BACKUP(1)