MAN page from Other dump-0.4b34-2sls.i586.rpm

RESTORE

Section: System management commands (8)
Updated: version 0.4b34 of April 18, 2003
Index

NAME

restore - restore files or file systems from backups made with dump

SYNOPSIS

restore -C [-cdklMvVy][-b blocksize][-D filesystem][-f file][-F script][-L limit][-s fileno][-T directory]

restore -i[-acdhklmMNouvVy][-A file][-b blocksize][-f file][-F script][-Q file][-s fileno][-T directory]

restore -P file[-acdhklmMNuvVy][-A file][-b blocksize][-f file][-F script][-s fileno][-T directory][-X filelist][ file ... ]

restore -R[-cdklMNuvVy][-b blocksize][-f file][-F script][-s fileno][-T directory]

restore -r [-cdklMNuvVy][-b blocksize][-f file][-F script][-s fileno][-T directory]

restore -t[-cdhklMNuvVy][-A file][-b blocksize][-f file][-F script][-Q file][-s fileno][-T directory][-X filelist][ file ... ]

restore -x [-adchklmMNouvVy][-A file][-b blocksize][-f file][-F script][-Q file][-s fileno][-T directory][-X filelist][ file ... ]

(The 4.3BSD option syntax is implemented for backward compatibility but is not documented here.)

DESCRIPTION

Therestorecommand performs the inverse function ofdump(8).A full backup of a file system may be restored and subsequent incrementalbackups layered on top of it. Single files and directory subtrees may be restored from full or partial backups.Restoreworks across a network; to do this see the-fflag described below. Other arguments to the command are file or directorynames specifying the files that are to be restored. Unless the-hflag is specified (see below), the appearance of a directory name refers tothe files and (recursively) subdirectories of that directory.

Exactly one of the following flags is required:

-C

This mode allows comparison of files from a dump.Restorereads the backup and compares its contents with files present on the disk. Itfirst changes its working directory to the root of the filesystem that was dumped and compares the tape with the files in its new current directory. Seealso the-Lflag described below.

-i

This mode allows interactive restoration of files from a dump. After reading inthe directory information from the dump,restoreprovides a shell like interface that allows the user to move around the directory tree selecting files to be extracted. The available commands are given below; for those commands that require an argument, the default is thecurrent directory.

add [arg]: The current directory or specified argument is added to the list of files to beextracted. If a directory is specified, then it and all its descendents areadded to the extraction list (unless the-hflag is specified on the command line). Files that are on the extraction listare prepended with a ``*'' when they are listed by ls.
cd arg: Change the current working directory to the specified argument.
delete [arg]: The current directory or specified argument is deleted from the list of files to be extracted. If a directory is specified, then it and all its descendentsare deleted from the extraction list (unless the-hflag is specified on the command line). The most expedient way to extract most of the files from a directory is to add the directory to the extraction listand then delete those files that are not needed.
extract: All files on the extraction list are extracted from the dump.Restorewill ask which volume the user wishes to mount. The fastest way to extract a few files is to start with the last volume and work towards the first volume.
help: List a summary of the available commands.
ls [arg]: List the current or specified directory. Entries that are directories are appended with a ``/''. Entries that have been marked for extraction are prepended with a ``*''. If the verbose flag is set, the inode number of each entry is also listed.
pwd: Print the full pathname of the current working directory.
quit: Restoreimmediately exits, even if the extraction list is not empty.
setmodes: All directories that have been added to the extraction list have their owner, modes, and times set; nothing is extracted from the dump. This is useful for cleaning up after a restore has been prematurely aborted.
verbose: The sense of the -vflag is toggled. When set, the verbose flag causes the lscommand to list the inode numbers of all entries. It also causesrestoreto print out information about each file as it is extracted.

-P file

Restorecreates a new Quick File Access file filefrom an existing dump file without restoring its contents.

-R

Restorerequests a particular tape of a multi-volume set on which to restart a full restore (see the-rflag below). This is useful if the restore has been interrupted.

-r

Restore (rebuild) a file system. The target file system should be made pristinewithmke2fs(8),mounted, and the usercd'dinto the pristine file system before starting the restoration of the initiallevel 0 backup. If the level 0 restores successfully, the-rflag may be used to restore any necessary incremental backups on top of thelevel 0. The-rflag precludes an interactive file extraction and can be detrimental to one's health (not to mention the disk) if not used carefully. An example:

mke2fs /dev/sda1

mount /dev/sda1 /mnt
cd /mnt
restore rf /dev/st0

Note that restoreleaves a file restoresymtablein the root directory to pass information between incremental restore passes.This file should be removed when the last incremental has been restored.

Restore,in conjunction withmke2fs(8)anddump(8),may be used to modify file system parameters such as size or block size.

-t

The names of the specified files are listed if they occur on the backup. If no file argument is given, the root directory is listed, which results in theentire content of the backup being listed, unless the-hflag has been specified. Note that the-tflag replaces the function of the olddumpdir(8)program. See also the-Xoption below.

-x

The named files are read from the given media. If a named file matches a directory whose contents are on the backup and the-hflag is not specified, the directory is recursively extracted. The owner, modification time, and mode are restored (if possible). If no file argument isgiven, the root directory is extracted, which results in the entire content ofthe backup being extracted, unless the-hflag has been specified. See also the-Xoption below.

OPTIONS

The following additional options may be specified:

-a: In -ior-xmode, restore does ask the user for the volume number on which the files to be extracted are supposed to be (in order to minimise the time by reading only the interesting volumes). The -aoption disables this behaviour and reads all the volumes starting with 1. This option is useful when the operator does not know on which volume the files to be extracted are and/or when he prefers the longer unattended mode rather thanthe shorter interactive mode.
-A archive_file: Read the table of contents fromarchive_fileinstead of the media. This option can be used in combination with the -t,-i,or -x options, making it possible to check whether files are on the media without having to mount the media.
-b blocksize: The number of kilobytes per dump record. If the-boption is not specified,restoretries to determine the media block size dynamically.
-c: Normally,restorewill try to determine dynamically whether the dump was made from an old (pre-4.4) or new format file system. The-cflag disables this check, and only allows reading a dump in the old format.
-d: The-d(debug) flag causesrestoreto print debug information.
-D filesystem: The-Dflag allows the user to specify the filesystem name when usingrestorewith the-Coption to check the backup.
-f file: Read the backup fromfile;filemay be a special device file like/dev/st0(a tape drive),/dev/sda1(a disk drive), an ordinary file, or-(the standard input). If the name of the file is of the formhost:file oruserAATThost:file,restorereads from the named file on the remote host usingrmt(8).
-F script: Run script at the beginning of each tape. The device name and the current volume number are passed on the command line. The script must return 0 if restoreshould continue without asking the user to change the tape, 1 if restoreshould continue but ask the user to change the tape. Any other exit code will causerestoreto abort. For security reasons,restorereverts back to the real user ID and the real group ID before running the script.
-h: Extract the actual directory, rather than the files that it references. This prevents hierarchical restoration of complete subtrees from the dump.
-k: Use Kerberos authentication when contacting the remote tape server. (Only available if this options was enabled whenrestorewas compiled.)
-l: When doing remote restores, assume the remote file is a regular file (insteadof a tape device). If you're restoring a remote compressed file, you will needto specify this option or restorewill fail to access it correctly.
-L limit: The-Lflag allows the user to specify a maximal number of miscompares when usingrestorewith the-Coption to check the backup. If this limit is reached, restorewill abort with an error message. A value of 0 (the default value) disables the check.
-m: Extract by inode numbers rather than by file name. This is useful if only a fewfiles are being extracted, and one wants to avoid regenerating the complete pathname to the file.
-M: Enables the multi-volume feature (for reading dumps made using the -Moption of dump). The name specified with-fis treated as a prefix andrestoretries to read in sequence from <prefix>001, <prefix>002 etc.
-N: The-Nflag causesrestoreto perform a full execution as requested by one of-i,-R,-r,torxcommand without actually writing any file on disk.
-o: The-oflag causesrestoreto automatically restore the current directory permissions without asking the operator whether to do so in one of-ior-xmodes.
-Q file: Use the filefilein order to read tape position as stored using the dump Quick File Access mode,in one of -i,-xor-tmode.
: It is recommended to set up the st driver to return logical tape positions rather than physical before calling dump/restorewith parameter -Q.Since not all tape devices support physical tape positions those tape devices return an error duringdump/restorewhen the st driver is set to the default physical setting. Please see thest(4)man page, option MTSETDRVBUFFER, or themt(1)man page, on how to set the driver to return logical tape positions.
: Before calling restorewith parameter -Q,always make sure the st driver is set to return the same type of tape positionused during the call todump.Otherwiserestoremay be confused.
: This option can be used when restoring from local or remote tapes (see above) or from local or remote files.
-s fileno: Read from the specifiedfilenoon a multi-file tape. File numbering starts at 1.
-T directory: The-Tflag allows the user to specify a directory to use for the storage of temporaryfiles. The default value is /tmp.This flag is most useful when restoring files after having booted from a floppy. There might be little or no space on the floppy filesystem, but anothersource of space might exist.
-u: When creating certain types of files, restoremay generate a warning diagnostic if they already exist in the target directory. To prevent this, the-u(unlink) flag causesrestoreto remove old entries before attempting to create new ones.
-v: Normallyrestoredoes its work silently. The-v(verbose) flag causes it to type the name of each file it treats preceded by its file type.
-V: Enables reading multi-volume non-tape mediums like CDROMs.
-X filelist: Read list of files to be listed or extracted from the text filefilelistin addition to those specified on the command line. This can be used in conjunction with the-tor-xcommands. The filefilelistshould contain file names separated by newlines.filelistmay be an ordinary file or-(the standard input).
-y: Do not ask the user whether to abort the restore in the event of an error.Always try to skip over the bad block(s) and continue.

DIAGNOSTICS

Complains if it gets a read error. If yhas been specified, or the user respondsy,restorewill attempt to continue the restore.

If a backup was made using more than one tape volume,restorewill notify the user when it is time to mount the next volume. If the-xor-iflag has been specified,restorewill also ask which volume the user wishes to mount. The fastest way to extracta few files is to start with the last volume, and work towards the first volume.

There are numerous consistency checks that can be listed byrestore.Most checks are self-explanatory or can ``never happen''. Common errorsare given below:

Converting to new file system format: A dump tape created from the old file system has been loaded. It isautomatically converted to the new file system format.
<filename>: not found on tape: The specified file name was listed in the tape directory, but was not found onthe tape. This is caused by tape read errors while looking for the file, andfrom using a dump tape created on an active file system.
expected next file <inumber>, got <inumber>: A file that was not listed in the directory showed up. This can occur whenusing a dump created on an active file system.
Incremental dump too low: When doing an incremental restore, a dump that was written before the previous incremental dump, or that has too low an incremental level has been loaded.
Incremental dump too high: When doing an incremental restore, a dump that does not begin its coveragewhere the previous incremental dump left off, or that has too high an incremental level has been loaded.
Tape read error while restoring <filename>
Tape read error while skipping over inode <inumber>
Tape read error while trying to resynchronize: A tape (or other media) read error has occurred. If a file name is specified,its contents are probably partially wrong. If an inode is being skipped or thetape is trying to resynchronize, no extracted files have been corrupted, thoughfiles may not be found on the tape.
resync restore, skipped <num> blocks: After a dump read error, restoremay have to resynchronize itself. This message lists the number of blocks thatwere skipped over.

EXIT STATUS

Restoreexits with zero status on success. Tape errors are indicated with an exit codeof 1.

When doing a comparison of files from a dump, an exit code of 2 indicates thatsome files were modified or deleted since the dump was made.

ENVIRONMENT

If the following environment variable exists it will be utilized byrestore:

TAPE: If no-foption was specified,restorewill use the device specified viaTAPEas the dump device.TAPEmay be of the formtapename,host:tapenameoruserAATThost:tapename.
TMPDIR: The directory given inTMPDIRwill be used instead of/tmpto store temporary files.
RMT: The environment variableRMTwill be used to determine the pathname of the remotermt(8)program.
RSH: Restoreuses the contents of this variable to determine the name of the remote shell command to use when doing a network restore (rsh, ssh etc.). If this variableis not set,rcmd(3)will be used, but only root will be able to do a network restore.

FILES

/dev/st0: the default tape drive
/tmp/rstdir*: file containing directories on the tape
/tmp/rstmode*: owner, mode, and time stamps for directories
./restoresymtable: information passed between incremental restores

BUGS

Restorecan get confused when doing incremental restores from dumps that were made onactive file systems.

A level 0 dump must be done after a full restore. Because restoreruns in user code, it has no control over inode allocation; thus a full dumpmust be done to get a new set of directories reflecting the new inode numbering, even though the content of the files is unchanged.

The temporary files/tmp/rstdir*and/tmp/rstmode*are generated with a unique name based on the date of the dump and the processID (seemktemp(3)),except when-ror-Ris used. Because-Rallows you to restart a-roperation that may have been interrupted, the temporary files should be the same across different processes. In all other cases, the files are unique because it is possible to have two different dumps started at the same time, and separate operations shouldn't conflict with each other.

To do a network restore, you have to run restoreas root or use a remote shell replacement (see RSHvariable). This is due to the previous security history of dump andrestore.(restoreis written to be setuid root, but we are not certain all bugs are gone from thecode - run setuid at your own risk.)

At the end of restores in-ior-xmodes (unless-ooption is in use),restorewill ask the operator whether to set the permissions on the currentdirectory. If the operator confirms this action, the permissions on the directory from where restorewas launched will be replaced by the permissions on the dumped rootinode. Although this behaviour is not really a bug, it has proven itselfto be confusing for many users, so it is recommended to answer 'no', unless you're performing a full restore and you do want to restore thepermissions on '/'.

AUTHOR

Thedump/restorebackup suite was ported to Linux's Second Extended File System by Remy Card <cardAATTLinux.EU.Org>. He maintained the initial versions of dump(up and including 0.4b4, released in january 1997).

Starting with 0.4b5, the new maintainer is Stelian Pop <stelianAATTpopies.net>.

AVAILABILITY

Thedump/restorebackup suite is available from <http://dump.sourceforge.net>

HISTORY

Therestorecommand appeared in 4.2BSD.

This document was created byman2html,using the manual pages.