1.\" $OpenBSD: restore.8,v 1.41 2022/03/31 17:27:20 naddy Exp $ 2.\" $NetBSD: restore.8,v 1.15 1997/07/01 05:37:53 lukem Exp $ 3.\" 4.\" Copyright (c) 1985, 1991, 1993 5.\" The Regents of the University of California. All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)restore.8 8.3 (Berkeley) 6/1/94 32.\" 33.Dd $Mdocdate: March 31 2022 $ 34.Dt RESTORE 8 35.Os 36.Sh NAME 37.Nm restore , 38.Nm rrestore 39.Nd restore files or file systems from backups made with dump 40.Sh SYNOPSIS 41.Nm restore 42.Op Fl chimRrtvxy 43.Op Fl b Ar blocksize 44.Op Fl f Ar file 45.Op Fl s Ar fileno 46.Op Ar 47.Sh DESCRIPTION 48The 49.Nm 50command performs the inverse function of 51.Xr dump 8 . 52A full backup of a file system may be restored and 53subsequent incremental backups layered on top of it. 54Single files and 55directory subtrees may be restored from full or partial 56backups. 57Other arguments to the command are file or directory 58names specifying the files that are to be restored. 59Unless the 60.Fl h 61flag is specified (see below), 62the appearance of a directory name refers to 63the files and (recursively) subdirectories of that directory. 64.Pp 65.Nm 66works across networks, 67replacing the functionality of the old 68.Nm rrestore 69program 70(though 71.Nm 72may still be invoked as 73.Nm rrestore ) . 74See the 75.Fl f 76option for more on reading backups from remote hosts. 77.Pp 78Exactly one of the following flags is required: 79.Bl -tag -width Ds 80.It Fl i 81This mode allows interactive restoration of files from a dump. 82After reading in the directory information from the dump, 83.Nm 84provides a shell like interface that allows the user to move 85around the directory tree selecting files to be extracted. 86The available commands are given below; 87for those commands that require an argument, 88the default is the current directory. 89.Bl -tag -width Fl 90.It Ic add Op Ar arg 91The current directory or specified argument is added to the list of 92files to be extracted. 93If a directory is specified, then it and all its descendants are 94added to the extraction list 95(unless the 96.Fl h 97flag is specified on the command line). 98Files that are on the extraction list are prepended with a 99.Dq \&* 100when they are listed by 101.Ic ls . 102.It Ic \&cd Ar arg 103Change the current working directory to the specified argument. 104.It Ic delete Op Ar arg 105The current directory or specified argument is deleted from the list of 106files to be extracted. 107If a directory is specified, then it and all its descendants are 108deleted from the extraction list 109(unless the 110.Fl h 111flag is specified on the command line). 112The most expedient way to extract most of the files from a directory 113is to add the directory to the extraction list and then delete 114those files that are not needed. 115.It Ic extract 116All files on the extraction list are extracted 117from the dump. 118.Nm 119will ask which volume the user wishes to mount. 120The fastest way to extract a few files is to 121start with the last volume and work towards the first volume. 122.It Ic help 123List a summary of the available commands. 124.It Ic \&ls Op Ar arg 125List the current or specified directory. 126Entries that are directories are appended with a 127.Dq / . 128Entries that have been marked for extraction are prepended with a 129.Dq \&* . 130If the verbose 131flag is set, the inode number of each entry is also listed. 132.It Ic pwd 133Print the full pathname of the current working directory. 134.It Ic quit 135Restore immediately exits, 136even if the extraction list is not empty. 137.It Ic setmodes 138All directories that have been added to the extraction list 139have their owner, modes, and times set; 140nothing is extracted from the dump. 141This is useful for cleaning up after a restore has been prematurely aborted. 142.It Ic verbose 143The sense of the 144.Fl v 145flag is toggled. 146When set, the verbose flag causes the 147.Ic ls 148command to list the inode numbers of all entries. 149It also causes 150.Nm 151to print out information about each file as it is extracted. 152.It Ic what 153List dump header information. 154.El 155.It Fl R 156.Nm 157requests a particular tape of a multi-volume set on which to restart 158a full restore 159(see the 160.Fl r 161flag below). 162This is useful if the restore has been interrupted. 163.It Fl r 164Restore (rebuild) a file system. 165The target file system should be made pristine with 166.Xr newfs 8 , 167mounted, and the user 168changed working directory 169into the pristine file system 170before starting the restoration of the initial level 0 backup. 171If the level 0 restores successfully, the 172.Fl r 173flag may be used to restore 174any necessary incremental backups on top of the level 0. 175The 176.Fl r 177flag precludes an interactive file extraction and can be 178detrimental to one's health (not to mention the disk) if not used carefully. 179An example of correct usage: 180.Bd -literal -offset indent 181# newfs /dev/rsd0g 182# mount /dev/sd0g /mnt 183# cd /mnt 184# restore rf /dev/rst0 185.Ed 186.Pp 187Note that 188.Nm 189leaves a file 190.Pa restoresymtable 191in the root directory to pass information between incremental 192restore passes. 193This file should be removed when the last incremental has been 194restored. 195.Pp 196.Nm restore , 197in conjunction with 198.Xr newfs 8 199and 200.Xr dump 8 , 201may be used to modify file system parameters 202such as size or block size. 203.It Fl t 204The names of the specified files are listed if they occur 205on the backup. 206If no file argument is given, 207the root directory is listed, 208which results in the entire content of the 209backup being listed, 210unless the 211.Fl h 212flag has been specified. 213Note that the 214.Fl t 215flag replaces the function of the old 216.Sy dumpdir 217program. 218.It Fl x 219The named files are read from the given media. 220If a named file matches a directory whose contents 221are on the backup 222and the 223.Fl h 224flag is not specified, 225the directory is recursively extracted. 226The owner, modification time, 227and mode are restored (if possible). 228If no file argument is given, 229the root directory is extracted, 230which results in the entire content of the 231backup being extracted, 232unless the 233.Fl h 234flag has been specified. 235.El 236.Pp 237The following additional options may be specified: 238.Bl -tag -width Ds 239.It Fl b Ar blocksize 240The number of kilobytes per dump record. 241If the 242.Fl b 243option is not specified, 244.Nm 245tries to determine the block size dynamically. 246.It Fl c 247Normally, 248.Nm 249will try to determine dynamically whether the dump was made from an 250old (pre-4.4) or new format file system. 251The 252.Fl c 253flag disables this check, and only allows reading a dump in the old 254format. 255.It Fl f Ar file 256Read the backup from 257.Ar file ; 258.Ar file 259may be a special device file 260like 261.Pa /dev/rst0 262(a tape drive), 263.Pa /dev/rsd1c 264(a disk drive), 265an ordinary file, 266or 267.Dq Fl 268(the standard input). 269If the name of the file is of the form 270.Dq host:file 271or 272.Dq user@host:file , 273.Nm 274reads from the named file on the remote host using 275.Xr rmt 8 . 276.It Fl h 277Extract the actual directory, 278rather than the files that it references. 279This prevents hierarchical restoration of complete subtrees 280from the dump. 281.It Fl m 282Extract by inode numbers rather than by file name. 283This is useful if only a few files are being extracted, 284and one wants to avoid regenerating the complete pathname 285to the file. 286.It Fl s Ar fileno 287Read from the specified 288.Ar fileno 289on a multi-file tape. 290File numbering starts at 1. 291.It Fl v 292Normally 293.Nm 294does its work silently. 295The 296.Fl v 297(verbose) 298flag causes it to type the name of each file it treats 299preceded by its file type. 300.It Fl y 301Do not ask the user whether to abort the restore in the event of an error. 302Always try to skip over the bad block(s) and continue. 303.El 304.Sh ENVIRONMENT 305If the following environment variable exists, it will be utilized by 306.Nm restore : 307.Bl -tag -width "TMPDIR" 308.It Ev TMPDIR 309The directory given in 310.Ev TMPDIR 311will be used 312instead of 313.Pa /tmp 314to store temporary files. 315Refer to 316.Xr environ 7 317for more information. 318.It Ev TAPE 319Default tape device to use instead of 320.Pa /dev/rst0 . 321.El 322.Sh FILES 323.Bl -tag -width "./restoresymtable" -compact 324.It Pa /dev/rst0 325the default tape drive 326.It Pa /dev/rst* 327raw SCSI tape interface 328.It Pa /tmp/rstdir* 329file containing directories on the tape 330.It Pa /tmp/rstmode* 331owner, mode, and time stamps for directories 332.It Pa \&./restoresymtable 333information passed between incremental restores 334.El 335.Sh DIAGNOSTICS 336Complains if it gets a read error. 337If 338.Fl y 339has been specified, or the user responds 340.Dq y , 341.Nm 342will attempt to continue the restore. 343.Pp 344If a backup was made using more than one tape volume, 345.Nm 346will notify the user when it is time to mount the next volume. 347If the 348.Fl x 349or 350.Fl i 351flag has been specified, 352.Nm 353will also ask which volume the user wishes to mount. 354The fastest way to extract a few files is to 355start with the last volume, and work towards the first volume. 356.Pp 357There are numerous consistency checks that can be listed by 358.Nm restore . 359Most checks are self-explanatory or can 360.Dq never happen . 361Common errors are given below. 362.Pp 363.Bl -tag -width Ds -compact 364.It Converting to new file system format 365A dump tape created from the old file system has been loaded. 366It is automatically converted to the new file system format. 367.Pp 368.It <filename>: not found on tape 369The specified file name was listed in the tape directory, 370but was not found on the tape. 371This is caused by tape read errors while looking for the file, 372and from using a dump tape created on an active file system. 373.Pp 374.It expected next file <inumber>, got <inumber> 375A file that was not listed in the directory showed up. 376This can occur when using a dump created on an active file system. 377.Pp 378.It Incremental dump too low 379When doing an incremental restore, 380a dump that was written before the previous incremental dump, 381or that has too low an incremental level has been loaded. 382.Pp 383.It Incremental dump too high 384When doing an incremental restore, 385a dump that does not begin its coverage where the previous incremental 386dump left off, 387or that has too high an incremental level has been loaded. 388.Pp 389.It Tape read error while restoring <filename> 390.It Tape read error while skipping over inode <inumber> 391.It Tape read error while trying to resynchronize 392A tape (or other media) read error has occurred. 393If a file name is specified, 394its contents are probably partially wrong. 395If an inode is being skipped or the tape is trying to resynchronize, 396no extracted files have been corrupted, 397though files may not be found on the tape. 398.Pp 399.It resync restore, skipped <num> blocks 400After a dump read error, 401.Nm 402may have to resynchronize itself. 403This message lists the number of blocks that were skipped over. 404.El 405.Sh SEE ALSO 406.Xr environ 7 , 407.Xr dump 8 , 408.Xr mount 8 , 409.Xr newfs 8 , 410.Xr rmt 8 411.Sh HISTORY 412The 413.Nm 414command appeared in 415.Bx 4.2 . 416.Pp 417The 418.Bx 4.3 419option syntax is implemented for backward compatibility but 420is not documented here. 421.Sh BUGS 422.Nm 423can get confused when doing incremental restores from 424dumps that were made on active file systems. 425.Pp 426A level 0 dump must be done after a full restore. 427Because 428.Nm 429runs in user mode, 430it has no control over inode allocation; 431thus a full dump must be done to get a new set of directories 432reflecting the new inode numbering, 433even though the content of the files is unchanged. 434.Pp 435The temporary files 436.Pa /tmp/rstdir* 437and 438.Pa /tmp/rstmode* 439are generated with a unique name based on the date of the dump 440and the process ID (see 441.Xr mktemp 3 ) , 442except when 443.Fl r 444or 445.Fl R 446is used. 447Because 448.Fl R 449allows you to restart a 450.Fl r 451operation that may have been interrupted, the temporary files should 452be the same across different processes. 453In all other cases, the files are unique because it is possible to 454have two different dumps started at the same time, and separate 455operations shouldn't conflict with each other. 456