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1227625a SP |
1 | .\" Copyright (c) 1980, 1991, 1993 |
2 | .\" Regents of the University of California. | |
3 | .\" All rights reserved. | |
4 | .\" | |
5 | .\" Redistribution and use in source and binary forms, with or without | |
6 | .\" modification, are permitted provided that the following conditions | |
7 | .\" are met: | |
8 | .\" 1. Redistributions of source code must retain the above copyright | |
9 | .\" notice, this list of conditions and the following disclaimer. | |
10 | .\" 2. Redistributions in binary form must reproduce the above copyright | |
11 | .\" notice, this list of conditions and the following disclaimer in the | |
12 | .\" documentation and/or other materials provided with the distribution. | |
13 | .\" 3. All advertising materials mentioning features or use of this software | |
ddd2ef55 | 14 | .\" must display the following acknowledgement: |
1227625a SP |
15 | .\" This product includes software developed by the University of |
16 | .\" California, Berkeley and its contributors. | |
17 | .\" 4. Neither the name of the University nor the names of its contributors | |
18 | .\" may be used to endorse or promote products derived from this software | |
19 | .\" without specific prior written permission. | |
20 | .\" | |
21 | .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |
22 | .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
23 | .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
24 | .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
25 | .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
26 | .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
27 | .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
28 | .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
29 | .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
30 | .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
31 | .\" SUCH DAMAGE. | |
32 | .\" | |
35b24fb7 | 33 | .\" $Id: dump.8.in,v 1.25 2001/04/10 12:46:53 stelian Exp $ |
1227625a | 34 | .\" |
8d4197bb | 35 | .Dd __DATE__ |
1227625a | 36 | .Dt DUMP 8 |
df9ae507 | 37 | .Os "dump __VERSION__" |
1227625a SP |
38 | .Sh NAME |
39 | .Nm dump | |
ddd2ef55 | 40 | .Nd ext2 filesystem backup |
1227625a SP |
41 | .Sh SYNOPSIS |
42 | .Nm dump | |
ce7243e0 | 43 | .Op Fl 0123456789ackMnSu |
1227625a SP |
44 | .Op Fl B Ar records |
45 | .Op Fl b Ar blocksize | |
46 | .Op Fl d Ar density | |
0d7af9c5 | 47 | .Op Fl e Ar inode number |
1227625a | 48 | .Op Fl f Ar file |
0d7af9c5 | 49 | .Op Fl F Ar script |
1227625a | 50 | .Op Fl h Ar level |
b45f51d6 | 51 | .Op Fl L Ar label |
35b24fb7 | 52 | .Op Fl Q Ar file |
1227625a SP |
53 | .Op Fl s Ar feet |
54 | .Op Fl T Ar date | |
ce7243e0 | 55 | .Op Fl z Ar compression level |
79e31865 | 56 | .Ar file-to-dump |
1227625a SP |
57 | .Nm dump |
58 | .Op Fl W Li \&| Fl w | |
59 | .Pp | |
8d4197bb | 60 | .in |
1227625a SP |
61 | (The |
62 | .Bx 4.3 | |
ddd2ef55 | 63 | option syntax is implemented for backward compatibility but |
1227625a SP |
64 | is not documented here.) |
65 | .Sh DESCRIPTION | |
66 | .Nm Dump | |
67 | examines files | |
ddd2ef55 | 68 | on an ext2 filesystem |
1227625a SP |
69 | and determines which files |
70 | need to be backed up. These files | |
71 | are copied to the given disk, tape or other | |
72 | storage medium for safe keeping (see the | |
73 | .Fl f | |
74 | option below for doing remote backups). | |
75 | A dump that is larger than the output medium is broken into | |
76 | multiple volumes. | |
77 | On most media the size is determined by writing until an | |
4f4eee3d | 78 | end-of-media indication is returned. |
b45f51d6 | 79 | .Pp |
1227625a | 80 | On media that cannot reliably return an end-of-media indication |
4f4eee3d SP |
81 | (such as some cartridge tape drives), each volume is of a fixed size; |
82 | the actual size is determined by specifying cartridge media, or via the | |
83 | tape size, density and/or block count options below. | |
1227625a SP |
84 | By default, the same output file name is used for each volume |
85 | after prompting the operator to change media. | |
86 | .Pp | |
79e31865 SP |
87 | .Ar file-to-dump |
88 | is either a mountpoint of a filesystem | |
89 | or a directory to be backed up as a subset of a filesystem. | |
90 | In the former case, either the path to a mounted filesystem | |
91 | or the device of an unmounted filesystem can be used. | |
92 | In the latter case, certain restrictions are placed on the backup: | |
93 | .Fl u | |
94 | is not allowed and the only dump level that is supported is | |
95 | .Fl 0 . | |
96 | .Pp | |
1227625a | 97 | The following options are supported by |
b45f51d6 | 98 | .Nm Ns : |
1227625a SP |
99 | .Bl -tag -width Ds |
100 | .It Fl 0\-9 | |
101 | Dump levels. | |
102 | A level 0, full backup, | |
103 | guarantees the entire file system is copied | |
104 | (but see also the | |
105 | .Fl h | |
106 | option below). | |
107 | A level number above 0, | |
108 | incremental backup, | |
ddd2ef55 SP |
109 | tells |
110 | .Nm dump | |
111 | to | |
1227625a | 112 | copy all files new or modified since the |
ae58c8da | 113 | last dump of a lower level. |
ddd2ef55 | 114 | The default level is 9. |
1227625a | 115 | .It Fl B Ar records |
aca7d867 | 116 | The number of 1 kB blocks per volume. |
4f4eee3d SP |
117 | This option overrides the end-of-media detection, and calculation |
118 | of tape size based on length and density. | |
b45f51d6 SP |
119 | .It Fl a |
120 | .Dq auto-size . | |
4f4eee3d SP |
121 | Bypass all tape length calculations, and write |
122 | until an end-of-media indication is returned. This works best | |
123 | for most modern tape drives, and is the default. | |
124 | Use of this option is particularly recommended when appending to an | |
125 | existing tape, or using a tape drive with hardware compression | |
126 | (where you can never be sure about the compression ratio). | |
1227625a SP |
127 | .It Fl b Ar blocksize |
128 | The number of kilobytes per dump record. | |
ddd2ef55 | 129 | Since the IO system slices all requests into chunks of MAXBSIZE |
aca7d867 | 130 | (typically 64kB), it is not possible to use a larger blocksize |
ddd2ef55 SP |
131 | without having problems later with |
132 | .Xr restore 8 . | |
133 | Therefore | |
134 | .Nm dump | |
135 | will constrain writes to MAXBSIZE. | |
65bceb9b | 136 | The default blocksize is 10. |
1227625a | 137 | .It Fl c |
b45f51d6 | 138 | Change the defaults for use with a cartridge tape drive, with a density |
4f4eee3d SP |
139 | of 8000 bpi, and a length of 1700 feet. Specifying a cartridge drive |
140 | overrides the end-of-media detection. | |
20c345aa SP |
141 | .It Fl e Ar inode |
142 | Exclude | |
143 | .Ar inode | |
144 | from the dump (you can use | |
145 | .Ar stat | |
146 | to find the inode number for a file or directory). | |
b45f51d6 SP |
147 | .It Fl h Ar level |
148 | Honor the user | |
149 | .Dq nodump | |
150 | flag | |
151 | .Dp Dv UF_NODUMP | |
152 | only for dumps at or above the given | |
153 | .Ar level . | |
154 | The default honor level is 1, | |
155 | so that incremental backups omit such files | |
156 | but full backups retain them. | |
1227625a SP |
157 | .It Fl d Ar density |
158 | Set tape density to | |
159 | .Ar density . | |
4f4eee3d SP |
160 | The default is 1600BPI. Specifying a tape density overrides the |
161 | end-of-media detection. | |
1227625a SP |
162 | .It Fl f Ar file |
163 | Write the backup to | |
164 | .Ar file ; | |
165 | .Ar file | |
166 | may be a special device file | |
167 | like | |
ddd2ef55 | 168 | .Pa /dev/st0 |
1227625a SP |
169 | (a tape drive), |
170 | .Pa /dev/rsd1c | |
b45f51d6 | 171 | (a floppy disk drive), |
1227625a SP |
172 | an ordinary file, |
173 | or | |
174 | .Ql Fl | |
175 | (the standard output). | |
176 | Multiple file names may be given as a single argument separated by commas. | |
177 | Each file will be used for one dump volume in the order listed; | |
178 | if the dump requires more volumes than the number of names given, | |
179 | the last file name will used for all remaining volumes after prompting | |
180 | for media changes. | |
181 | If the name of the file is of the form | |
ddd2ef55 | 182 | .Dq host:file |
1227625a | 183 | or |
ddd2ef55 | 184 | .Dq user@host:file |
b45f51d6 | 185 | .Nm |
1227625a SP |
186 | writes to the named file on the remote host using |
187 | .Xr rmt 8 . | |
b45f51d6 SP |
188 | The default path name of the remote |
189 | .Xr rmt 8 | |
190 | program is | |
191 | .\" rmt path, is the path on the remote host | |
192 | .Pa /etc/rmt ; | |
193 | this can be overridden by the environment variable | |
194 | .Ev RMT . | |
0d7af9c5 | 195 | .It Fl F Ar script |
365a7c7c SP |
196 | Run script at the end of each tape. The device name and the |
197 | current volume number are passed on the command line. | |
198 | The script must return 0 if | |
ae81b200 SP |
199 | .Nm |
200 | should continue without asking the user to change the tape, 1 if | |
201 | .Nm | |
202 | dump should continue but ask the user to change the tape. | |
203 | Any other exit code will cause | |
204 | .Nm | |
205 | to abort. | |
206 | For security reasons, | |
207 | .Nm | |
208 | reverts back to the real user ID and the real group ID before | |
209 | running the script. | |
b45f51d6 SP |
210 | .It Fl k |
211 | Use Kerberos authentication to talk to remote tape servers. (Only | |
212 | available if this option was enabled when | |
213 | .Nm | |
214 | was compiled.) | |
215 | .It Fl L Ar label | |
216 | The user-supplied text string | |
217 | .Ar label | |
218 | is placed into the dump header, where tools like | |
219 | .Xr restore 8 | |
220 | and | |
221 | .Xr file 1 | |
222 | can access it. | |
223 | Note that this label is limited | |
224 | to be at most LBLSIZE (currently 16) characters, which must include | |
225 | the terminating | |
226 | .Ql \e0 . | |
dc7cb1e2 SP |
227 | .It Fl M |
228 | Enable the multi-volume feature. The name specified with | |
229 | .Fl f | |
230 | is treated as a prefix and | |
231 | .Nm | |
232 | writes in sequence to <prefix>001, <prefix>002 etc. This can be | |
233 | useful when dumping to files on an ext2 partition, in order to bypass | |
234 | the 2GB file size limitation. | |
1227625a SP |
235 | .It Fl n |
236 | Whenever | |
b45f51d6 | 237 | .Nm |
1227625a SP |
238 | requires operator attention, |
239 | notify all operators in the group | |
240 | .Dq operator | |
241 | by means similar to a | |
242 | .Xr wall 1 . | |
35b24fb7 SP |
243 | .It Fl Q Ar file |
244 | Enable the Quick File Access support. Tape positions for each | |
245 | inode are stored into the file | |
246 | .Ar file | |
247 | which is used by restore (if called with parameter Q and the filename) | |
248 | to directly position the tape at the file restore is currently working | |
249 | on. This saves hours when restoring single files from large backups, | |
250 | saves the tapes and the drive's head. | |
1227625a | 251 | .It Fl s Ar feet |
4f4eee3d | 252 | Attempt to calculate the amount of tape needed at a particular density. |
1227625a | 253 | If this amount is exceeded, |
b45f51d6 | 254 | .Nm |
1227625a SP |
255 | prompts for a new tape. |
256 | It is recommended to be a bit conservative on this option. | |
4f4eee3d SP |
257 | The default tape length is 2300 feet. Specifying the tape size |
258 | overrides end-of-media detection. | |
1227625a | 259 | .ne 1i |
144a6db1 SP |
260 | .It Fl S |
261 | Size estimate. Determine the amount of space | |
262 | that is needed to perform the dump without | |
263 | actually doing it, and display the estimated | |
2e682895 | 264 | number of bytes it will take. This is useful |
144a6db1 SP |
265 | with incremental dumps to determine how many |
266 | volumes of media will be needed. | |
1227625a SP |
267 | .It Fl T Ar date |
268 | Use the specified date as the starting time for the dump | |
269 | instead of the time determined from looking in | |
8d4197bb | 270 | .Pa __DUMPDATES__ . |
ddd2ef55 SP |
271 | The format of |
272 | .Ar date | |
273 | is the same as that of | |
1227625a SP |
274 | .Xr ctime 3 . |
275 | This option is useful for automated dump scripts that wish to | |
276 | dump over a specific period of time. | |
277 | The | |
278 | .Fl T | |
279 | option is mutually exclusive from the | |
280 | .Fl u | |
281 | option. | |
282 | .It Fl u | |
283 | Update the file | |
8d4197bb | 284 | .Pa __DUMPDATES__ |
1227625a SP |
285 | after a successful dump. |
286 | The format of | |
8d4197bb | 287 | .Pa __DUMPDATES__ |
1227625a SP |
288 | is readable by people, consisting of one |
289 | free format record per line: | |
290 | filesystem name, | |
291 | increment level | |
292 | and | |
293 | .Xr ctime 3 | |
294 | format dump date. | |
295 | There may be only one entry per filesystem at each level. | |
296 | The file | |
8d4197bb | 297 | .Pa __DUMPDATES__ |
1227625a SP |
298 | may be edited to change any of the fields, |
299 | if necessary. | |
300 | .It Fl W | |
301 | .Nm Dump | |
302 | tells the operator what file systems need to be dumped. | |
303 | This information is gleaned from the files | |
8d4197bb | 304 | .Pa __DUMPDATES__ |
1227625a SP |
305 | and |
306 | .Pa /etc/fstab . | |
307 | The | |
308 | .Fl W | |
309 | option causes | |
b45f51d6 | 310 | .Nm |
51b01afe | 311 | to print out, for all file systems in |
8d4197bb | 312 | .Pa __DUMPDATES__ , |
51b01afe SP |
313 | and regognized file systems in |
314 | .Pa /etc/fstab . | |
1227625a | 315 | the most recent dump date and level, |
51b01afe | 316 | and highlights those that should be dumped. |
1227625a SP |
317 | If the |
318 | .Fl W | |
319 | option is set, all other options are ignored, and | |
b45f51d6 | 320 | .Nm |
1227625a SP |
321 | exits immediately. |
322 | .It Fl w | |
ddd2ef55 SP |
323 | Is like |
324 | .Fl W , | |
51b01afe SP |
325 | but prints only recognized filesystems in |
326 | .Pa /etc/fstab | |
327 | which need to be dumped. | |
ce7243e0 | 328 | .It Fl z Ar compression level |
52ed7d6e | 329 | Compress every block to be written on the tape using zlib library. This |
2b747532 SP |
330 | option will work only when dumping to a file or pipe or, when dumping |
331 | to a tape drive, if the tape drive is capable of writing variable | |
52ed7d6e SP |
332 | length blocks. You will need at least the 0.4b22 version of restore in |
333 | order to extract compressed tapes. Tapes written using compression will | |
ce7243e0 SP |
334 | not be compatible with the BSD tape format. The (optional) parameter |
335 | specifies the compression level zlib will use. The default compression | |
336 | level is 2. | |
1227625a SP |
337 | .El |
338 | .Pp | |
339 | .Nm Dump | |
340 | requires operator intervention on these conditions: | |
341 | end of tape, | |
342 | end of dump, | |
343 | tape write error, | |
344 | tape open error or | |
ddd2ef55 | 345 | disk read error (if there is more than a threshold of 32). |
1227625a SP |
346 | In addition to alerting all operators implied by the |
347 | .Fl n | |
348 | key, | |
b45f51d6 | 349 | .Nm |
1227625a SP |
350 | interacts with the operator on |
351 | .Em dump's | |
352 | control terminal at times when | |
b45f51d6 | 353 | .Nm |
1227625a SP |
354 | can no longer proceed, |
355 | or if something is grossly wrong. | |
356 | All questions | |
b45f51d6 | 357 | .Nm |
1227625a SP |
358 | poses |
359 | .Em must | |
360 | be answered by typing | |
361 | .Dq yes | |
362 | or | |
363 | .Dq no , | |
364 | appropriately. | |
365 | .Pp | |
366 | Since making a dump involves a lot of time and effort for full dumps, | |
b45f51d6 | 367 | .Nm |
1227625a SP |
368 | checkpoints itself at the start of each tape volume. |
369 | If writing that volume fails for some reason, | |
b45f51d6 | 370 | .Nm |
1227625a SP |
371 | will, |
372 | with operator permission, | |
373 | restart itself from the checkpoint | |
374 | after the old tape has been rewound and removed, | |
375 | and a new tape has been mounted. | |
376 | .Pp | |
377 | .Nm Dump | |
378 | tells the operator what is going on at periodic intervals, | |
379 | including usually low estimates of the number of blocks to write, | |
380 | the number of tapes it will take, the time to completion, and | |
381 | the time to the tape change. | |
382 | The output is verbose, | |
383 | so that others know that the terminal | |
384 | controlling | |
b45f51d6 | 385 | .Nm |
1227625a SP |
386 | is busy, |
387 | and will be for some time. | |
388 | .Pp | |
389 | In the event of a catastrophic disk event, the time required | |
390 | to restore all the necessary backup tapes or files to disk | |
391 | can be kept to a minimum by staggering the incremental dumps. | |
392 | An efficient method of staggering incremental dumps | |
393 | to minimize the number of tapes follows: | |
394 | .Bl -bullet -offset indent | |
395 | .It | |
396 | Always start with a level 0 backup, for example: | |
397 | .Bd -literal -offset indent | |
8d4197bb | 398 | /sbin/dump -0u -f /dev/st0 /usr/src |
1227625a SP |
399 | .Ed |
400 | .Pp | |
401 | This should be done at set intervals, say once a month or once every two months, | |
402 | and on a set of fresh tapes that is saved forever. | |
403 | .It | |
404 | After a level 0, dumps of active file | |
405 | systems are taken on a daily basis, | |
406 | using a modified Tower of Hanoi algorithm, | |
407 | with this sequence of dump levels: | |
408 | .Bd -literal -offset indent | |
409 | 3 2 5 4 7 6 9 8 9 9 ... | |
410 | .Ed | |
411 | .Pp | |
412 | For the daily dumps, it should be possible to use a fixed number of tapes | |
413 | for each day, used on a weekly basis. | |
414 | Each week, a level 1 dump is taken, and | |
415 | the daily Hanoi sequence repeats beginning with 3. | |
416 | For weekly dumps, another fixed set of tapes per dumped file system is | |
417 | used, also on a cyclical basis. | |
418 | .El | |
419 | .Pp | |
420 | After several months or so, the daily and weekly tapes should get | |
421 | rotated out of the dump cycle and fresh tapes brought in. | |
b45f51d6 SP |
422 | .Sh ENVIRONMENT |
423 | .Bl -tag -width Fl | |
424 | .It Ev TAPE | |
425 | If no -f option was specified, | |
426 | .Nm | |
427 | will use the device specified via | |
428 | .Ev TAPE | |
429 | as the dump device. | |
430 | .Ev TAPE | |
431 | may be of the form | |
432 | .Qq tapename , | |
433 | .Qq host:tapename , | |
434 | or | |
435 | .Qq user@host:tapename . | |
436 | .It Ev RMT | |
437 | The environment variable | |
438 | .Ev RMT | |
439 | will be used to determine the pathname of the remote | |
440 | .Xr rmt 8 | |
441 | program. | |
0c62667d SP |
442 | .It Ev RSH |
443 | .Nm Dump | |
444 | uses the contents of this variable to determine the name of the | |
445 | remote shell command to use when doing remote backups (rsh, ssh etc.). | |
446 | If this variable is not set, | |
447 | .Xr rcmd 3 | |
448 | will be used, but only root will be able to do remote backups. | |
1227625a | 449 | .Sh FILES |
8d4197bb | 450 | .Bl -tag -width __DUMPDATES__ -compact |
ddd2ef55 | 451 | .It Pa /dev/st0 |
1227625a | 452 | default tape unit to dump to |
8d4197bb | 453 | .It Pa __DUMPDATES__ |
1227625a SP |
454 | dump date records |
455 | .It Pa /etc/fstab | |
456 | dump table: file systems and frequency | |
457 | .It Pa /etc/group | |
458 | to find group | |
459 | .Em operator | |
460 | .El | |
461 | .Sh SEE ALSO | |
b45f51d6 | 462 | .Xr fstab 5 , |
1227625a | 463 | .Xr restore 8 , |
b45f51d6 | 464 | .Xr rmt 8 |
1227625a SP |
465 | .Sh DIAGNOSTICS |
466 | Many, and verbose. | |
467 | .Pp | |
ddd2ef55 SP |
468 | .Nm Dump |
469 | exits with zero status on success. | |
1227625a SP |
470 | Startup errors are indicated with an exit code of 1; |
471 | abnormal termination is indicated with an exit code of 3. | |
472 | .Sh BUGS | |
ddd2ef55 SP |
473 | It might be considered a bug that this version of dump can only handle ext2 |
474 | filesystems. Specifically, it does not work with FAT filesystems. | |
475 | .Pp | |
476 | Fewer than 32 read errors on the filesystem are ignored. If noticing | |
477 | read errors is important, the output from dump can be parsed to look for lines | |
478 | that contain the text 'read error'. | |
1227625a SP |
479 | .Pp |
480 | Each reel requires a new process, so parent processes for | |
481 | reels already written just hang around until the entire tape | |
482 | is written. | |
483 | .Pp | |
1227625a | 484 | It would be nice if |
b45f51d6 | 485 | .Nm |
1227625a SP |
486 | knew about the dump sequence, |
487 | kept track of the tapes scribbled on, | |
488 | told the operator which tape to mount when, | |
489 | and provided more assistance | |
490 | for the operator running | |
491 | .Xr restore . | |
b45f51d6 SP |
492 | .Pp |
493 | .Nm Dump | |
494 | cannot do remote backups without being run as root, due to its | |
0c62667d | 495 | security history. |
b45f51d6 | 496 | Presently, it works if you set it setuid (like it used to be), but this |
0c62667d SP |
497 | might constitute a security risk. Note that you can set RSH to use |
498 | a remote shell program instead. | |
8d4197bb SP |
499 | .Sh AUTHOR |
500 | The | |
501 | .Nm dump/restore | |
7422942f | 502 | backup suite was ported to Linux's Second Extended File System |
8d4197bb SP |
503 | by Remy Card <card@Linux.EU.Org>. He maintained the initial versions |
504 | of dump (up and including 0.4b4, released in january 1997). | |
505 | .Pp | |
506 | Starting with 0.4b5, the new maintainer is Stelian Pop | |
507 | .br | |
109e9e1d | 508 | <pop@noos.fr>. |
8d4197bb SP |
509 | .Sh AVAILABILITY |
510 | The | |
511 | .Nm dump/restore | |
7422942f | 512 | backup suite is available from |
01fb6bd5 SP |
513 | .br |
514 | http://dump.sourceforge.net | |
1227625a SP |
515 | .Sh HISTORY |
516 | A | |
b45f51d6 SP |
517 | .Nm |
518 | command appeared in | |
519 | .At v6 . |