xref: /freebsd/sbin/restore/restore.8 (revision ce834215a70ff69e7e222827437116eee2f9ac6f)
1.\" Copyright (c) 1985, 1991, 1993
2.\"	The Regents of the University of California.  All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\"    notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\"    notice, this list of conditions and the following disclaimer in the
11.\"    documentation and/or other materials provided with the distribution.
12.\" 3. All advertising materials mentioning features or use of this software
13.\"    must display the following acknowledgement:
14.\"	This product includes software developed by the University of
15.\"	California, Berkeley and its contributors.
16.\" 4. Neither the name of the University nor the names of its contributors
17.\"    may be used to endorse or promote products derived from this software
18.\"    without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
32.\"     @(#)restore.8	8.4 (Berkeley) 5/1/95
33.\"	$Id: restore.8,v 1.10 1997/03/11 12:55:16 peter Exp $
34.\"
35.Dd May 1, 1995
36.Dt RESTORE 8
37.Os BSD 4
38.Sh NAME
39.Nm restore
40.Nd "restore files or file systems from backups made with dump"
41.Sh SYNOPSIS
42.Nm restore
43.Fl i
44.Op Fl chkmvy
45.Op Fl b Ar blocksize
46.Op Fl f Ar file
47.Op Fl s Ar fileno
48.Nm restore
49.Fl R
50.Op Fl ckvy
51.Op Fl b Ar blocksize
52.Op Fl f Ar file
53.Op Fl s Ar fileno
54.Nm restore
55.Fl r
56.Op Fl ckvy
57.Op Fl b Ar blocksize
58.Op Fl f Ar file
59.Op Fl s Ar fileno
60.Nm restore
61.Fl t
62.Op Fl chkvy
63.Op Fl b Ar blocksize
64.Op Fl f Ar file
65.Op Fl s Ar fileno
66.Op file ...
67.Nm restore
68.Fl x
69.Op Fl chkmvy
70.Op Fl b Ar blocksize
71.Op Fl f Ar file
72.Op Fl s Ar fileno
73.Op file ...
74.Pp
75.in -\\n(iSu
76(The
77.Bx 4.3
78option syntax is implemented for backward compatibility, but
79is not documented here.)
80.Sh DESCRIPTION
81The
82.Nm restore
83command performs the inverse function of
84.Xr dump 8 .
85A full backup of a file system may be restored and
86subsequent incremental backups layered on top of it.
87Single files and
88directory subtrees may be restored from full or partial
89backups.
90.Nm Restore
91works across a network;
92to do this see the
93.Fl f
94flag described below.
95Other arguments to the command are file or directory
96names specifying the files that are to be restored.
97Unless the
98.Fl h
99flag is specified (see below),
100the appearance of a directory name refers to
101the files and (recursively) subdirectories of that directory.
102.Pp
103Exactly one of the following flags is required:
104.Bl -tag -width Ds
105.It Fl i
106This mode allows interactive restoration of files from a dump.
107After reading in the directory information from the dump,
108.Nm restore
109provides a shell like interface that allows the user to move
110around the directory tree selecting files to be extracted.
111The available commands are given below;
112for those commands that require an argument,
113the default is the current directory.
114.Bl -tag -width Fl
115.It Ic add Op Ar arg
116The current directory or specified argument is added to the list of
117files to be extracted.
118If a directory is specified, then it and all its descendents are
119added to the extraction list
120(unless the
121.Fl h
122flag is specified on the command line).
123Files that are on the extraction list are prepended with a ``*''
124when they are listed by
125.Ic ls .
126.It Ic \&cd Ar arg
127Change the current working directory to the specified argument.
128.It Ic delete Op Ar arg
129The current directory or specified argument is deleted from the list of
130files to be extracted.
131If a directory is specified, then it and all its descendents are
132deleted from the extraction list
133(unless the
134.Fl h
135flag is specified on the command line).
136The most expedient way to extract most of the files from a directory
137is to add the directory to the extraction list and then delete
138those files that are not needed.
139.It Ic extract
140All the files that are on the extraction list are extracted
141from the dump.
142.Nm Restore
143will ask which volume the user wishes to mount.
144The fastest way to extract a few files is to
145start with the last volume, and work towards the first volume.
146.It Ic help
147List a summary of the available commands.
148.It Ic \&ls Op Ar arg
149List the current or specified directory.
150Entries that are directories are appended with a ``/''.
151Entries that have been marked for extraction are prepended with a ``*''.
152If the verbose
153flag is set the inode number of each entry is also listed.
154.It Ic pwd
155Print the full pathname of the current working directory.
156.It Ic quit
157Restore immediately exits,
158even if the extraction list is not empty.
159.It Ic setmodes
160All the directories that have been added to the extraction list
161have their owner, modes, and times set;
162nothing is extracted from the dump.
163This is useful for cleaning up after a restore has been prematurely aborted.
164.It Ic verbose
165The sense of the
166.Fl v
167flag is toggled.
168When set, the verbose flag causes the
169.Ic ls
170command to list the inode numbers of all entries.
171It also causes
172.Nm restore
173to print out information about each file as it is extracted.
174.El
175.It Fl R
176.Nm Restore
177requests a particular tape of a multi volume set on which to restart
178a full restore
179(see the
180.Fl r
181flag below).
182This is useful if the restore has been interrupted.
183.It Fl r
184Restore (rebuild a file system).
185The target file system should be made pristine with
186.Xr newfs 8 ,
187mounted and the user
188.Xr cd Ns 'd
189into the pristine file system
190before starting the restoration of the initial level 0 backup. If the
191level 0 restores successfully, the
192.Fl r
193flag may be used to restore
194any necessary incremental backups on top of the level 0.
195The
196.Fl r
197flag precludes an interactive file extraction and can be
198detrimental to one's health if not used carefully (not to mention
199the disk). An example:
200.Bd -literal -offset indent
201newfs /dev/rrp0g eagle
202mount /dev/rp0g /mnt
203cd /mnt
204
205restore rf /dev/rst8
206.Ed
207.Pp
208Note that
209.Nm restore
210leaves a file
211.Pa restoresymtable
212in the root directory to pass information between incremental
213restore passes.
214This file should be removed when the last incremental has been
215restored.
216.Pp
217.Nm Restore ,
218in conjunction with
219.Xr newfs 8
220and
221.Xr dump 8 ,
222may be used to modify file system parameters
223such as size or block size.
224.It Fl t
225The names of the specified files are listed if they occur
226on the backup.
227If no file argument is given,
228then the root directory is listed,
229which results in the entire content of the
230backup being listed,
231unless the
232.Fl h
233flag has been specified.
234Note that the
235.Fl t
236flag replaces the function of the old
237.Xr dumpdir 8
238program.
239.ne 1i
240.It Fl x
241The named files are read from the given media.
242If a named file matches a directory whose contents
243are on the backup
244and the
245.Fl h
246flag is not specified,
247the directory is recursively extracted.
248The owner, modification time,
249and mode are restored (if possible).
250If no file argument is given,
251then the root directory is extracted,
252which results in the entire content of the
253backup being extracted,
254unless the
255.Fl h
256flag has been specified.
257.El
258.Pp
259The following additional options may be specified:
260.Bl -tag -width Ds
261.It Fl b Ar blocksize
262The number of kilobytes per dump record.
263If the
264.Fl b
265option is not specified,
266.Nm restore
267tries to determine the media block size dynamically.
268.It Fl c
269Normally,
270.Nm restore
271will try to determine dynamically whether the dump was made from an
272old (pre-4.4) or new format file sytem.  The
273.Fl c
274flag disables this check, and only allows reading a dump in the old
275format.
276.It Fl f Ar file
277Read the backup from
278.Ar file ;
279.Ar file
280may be a special device file
281like
282.Pa /dev/rmt12
283(a tape drive),
284.Pa /dev/rsd1c
285(a disk drive),
286an ordinary file,
287or
288.Ql Fl
289(the standard input).
290If the name of the file is of the form
291.Dq host:file ,
292or
293.Dq user@host:file ,
294.Nm restore
295reads from the named file on the remote host using
296.Xr rmt 8 .
297.Pp
298.It Fl k
299Use Kerberos authentication when contacting the remote tape server.
300(Only available if this options was enabled when
301.Nm restore
302was compiled.)
303.Pp
304.It Fl h
305Extract the actual directory,
306rather than the files that it references.
307This prevents hierarchical restoration of complete subtrees
308from the dump.
309.It Fl m
310Extract by inode numbers rather than by file name.
311This is useful if only a few files are being extracted,
312and one wants to avoid regenerating the complete pathname
313to the file.
314.It Fl s Ar fileno
315Read from the specified
316.Ar fileno
317on a multi-file tape.
318File numbering starts at 1.
319.It Fl v
320Normally
321.Nm restore
322does its work silently.
323The
324.Fl v
325(verbose)
326flag causes it to type the name of each file it treats
327preceded by its file type.
328.It Fl y
329Do not ask the user whether to abort the restore in the event of an error.
330Always try to skip over the bad block(s) and continue.
331.El
332.Sh DIAGNOSTICS
333Complaints if it gets a read error.
334If
335.Fl y
336has been specified, or the user responds
337.Ql y ,
338.Nm restore
339will attempt to continue the restore.
340.Pp
341If a backup was made using more than one tape volume,
342.Nm restore
343will notify the user when it is time to mount the next volume.
344If the
345.Fl x
346or
347.Fl i
348flag has been specified,
349.Nm restore
350will also ask which volume the user wishes to mount.
351The fastest way to extract a few files is to
352start with the last volume, and work towards the first volume.
353.Pp
354There are numerous consistency checks that can be listed by
355.Nm restore .
356Most checks are self-explanatory or can ``never happen''.
357Common errors are given below.
358.Pp
359.Bl -tag -width Ds -compact
360.It Converting to new file system format.
361A dump tape created from the old file system has been loaded.
362It is automatically converted to the new file system format.
363.Pp
364.It <filename>: not found on tape
365The specified file name was listed in the tape directory,
366but was not found on the tape.
367This is caused by tape read errors while looking for the file,
368and from using a dump tape created on an active file system.
369.Pp
370.It expected next file <inumber>, got <inumber>
371A file that was not listed in the directory showed up.
372This can occur when using a dump created on an active file system.
373.Pp
374.It Incremental dump too low
375When doing incremental restore,
376a dump that was written before the previous incremental dump,
377or that has too low an incremental level has been loaded.
378.Pp
379.It Incremental dump too high
380When doing incremental restore,
381a dump that does not begin its coverage where the previous incremental
382dump left off,
383or that has too high an incremental level has been loaded.
384.Pp
385.It Tape read error while restoring <filename>
386.It Tape read error while skipping over inode <inumber>
387.It Tape read error while trying to resynchronize
388A tape (or other media) read error has occurred.
389If a file name is specified,
390then its contents are probably partially wrong.
391If an inode is being skipped or the tape is trying to resynchronize,
392then no extracted files have been corrupted,
393though files may not be found on the tape.
394.Pp
395.It resync restore, skipped <num> blocks
396After a dump read error,
397.Nm restore
398may have to resynchronize itself.
399This message lists the number of blocks that were skipped over.
400.El
401.Sh FILES
402.Bl -tag -width "./restoresymtable" -compact
403.It Pa /dev/rst0
404the default tape drive
405.It Pa /tmp/rstdir*
406file containing directories on the tape.
407.It Pa /tmp/rstmode*
408owner, mode, and time stamps for directories.
409.It Pa \&./restoresymtable
410information passed between incremental restores.
411.El
412.Sh SEE ALSO
413.Xr dump 8 ,
414.Xr ft 8 ,
415.Xr mount 8 ,
416.Xr newfs 8 ,
417.Xr rmt 8
418.Sh BUGS
419.Nm Restore
420can get confused when doing incremental restores from
421dumps that were made on active file systems.
422.Pp
423A level zero dump must be done after a full restore.
424Because restore runs in user code,
425it has no control over inode allocation;
426thus a full dump must be done to get a new set of directories
427reflecting the new inode numbering,
428even though the contents of the files is unchanged.
429.Pp
430To do a network restore, you have to run restore as root.  This is due
431to the previous security history of dump and restore.  (restore is
432written to be setuid root, but we are not certain all bugs are gone
433from the restore code - run setuid at your own risk.)
434.Sh HISTORY
435The
436.Nm restore
437command appeared in
438.Bx 4.2 .
439