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RESTORE(8) FreeBSD System Manager's Manual RESTORE(8)
NAME
restore, rrestore - restore files or file systems from backups made with
dump
SYNOPSIS
restore -i [-dDhmNuvy] [-b blocksize] [-f file | -P pipecommand]
[-s fileno]
restore -R [-dDNuvy] [-b blocksize] [-f file | -P pipecommand]
[-s fileno]
restore -r [-dDNuvy] [-b blocksize] [-f file | -P pipecommand]
[-s fileno]
restore -t [-dDhNuvy] [-b blocksize] [-f file | -P pipecommand]
[-s fileno] [file ...]
restore -x [-dDhmNuvy] [-b blocksize] [-f file | -P pipecommand]
[-s fileno] [file ...]
DESCRIPTION
The restore utility performs the inverse function of dump(8). A full
backup of a file system may be restored and subsequent incremental
backups layered on top of it. Single files and directory subtrees may be
restored from full or partial backups. The restore utility works across
a network; to do this see the -f and -P flags described below. Other
arguments to the command are file or directory names specifying the files
that are to be restored. Unless the -h flag is specified (see below),
the appearance of a directory name refers to the files and (recursively)
subdirectories of that directory.
restore may also be invoked as rrestore. The 4.3BSD option syntax is
implemented for backward compatibility, but is not documented here.
Exactly one of the following flags is required:
-i This mode allows interactive restoration of files from a dump.
After reading in the directory information from the dump, restore
provides 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 the current directory.
add [arg] The current directory or specified argument is added
to the list of files to be extracted. If a directory
is specified, then it and all its descendents are
added to the extraction list (unless the -h flag is
specified on the command line). Files that are on
the extraction list are 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
descendents are deleted from the extraction list
(unless the -h flag is specified on the command
line). The most expedient way to extract most of 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 Exit immediately, even if the extraction list is not
empty.
setmodes All the 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 -v flag is toggled. When set, the
verbose flag causes the ls command to list the inode
numbers of all entries. It also causes restore to
print out information about each file as it is
extracted.
what Display dump header information, which includes:
date, level, label, and the file system and host dump
was made from.
-R Request a particular tape of a multi volume set on which to
restart a full restore (see the -r flag below). This is useful
if the restore has been interrupted.
-r Restore (rebuild a file system). The target file system should
be made pristine with newfs(8), mounted and the user cd(1)'d into
the pristine file system before starting the restoration of the
initial level 0 backup. If the level 0 restores successfully,
the -r flag may be used to restore any necessary incremental
backups on top of the level 0. The -r flag precludes an
interactive file extraction and can be detrimental to one's
health if not used carefully (not to mention the disk). An
example:
newfs /dev/da0s1a
mount /dev/da0s1a /mnt
cd /mnt
restore rf /dev/sa0
Note that restore leaves a file restoresymtable in the root
directory to pass information between incremental restore passes.
This file should be removed when the last incremental has been
restored.
The restore utility , in conjunction with newfs(8) and dump(8),
flag replaces the function of the old dumpdir(8) program.
-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 -h
flag is not specified, the directory is recursively extracted.
The owner, modification time, and mode are restored (if
possible). If no file argument is given, then the root directory
is extracted, which results in the entire content of the backup
being extracted, unless the -h flag has been specified.
The following additional options may be specified:
-b blocksize
The number of kilobytes per dump record. If the -b option is not
specified, restore tries to determine the media block size
dynamically.
-d Sends verbose debugging output to the standard error.
-D This puts restore into degraded mode, causing restore to operate
less efficiently but to try harder to read corrupted backups.
-f file
Read the backup from file; file may be a special device file like
/dev/sa0 (a tape drive), /dev/da1c (a disk drive), an ordinary
file, or `-' (the standard input). If the name of the file is of
the form "host:file", or "user@host:file", restore reads from the
named file on the remote host using rmt(8).
-P pipecommand
Use popen(3) to execute the sh(1) script string defined by
pipecommand as the input for every volume in the backup. This
child pipeline's stdout (/dev/fd/1) is redirected to the restore
input stream, and the environment variable RESTORE_VOLUME is set
to the current volume number being read. The pipecommand script
is started each time a volume is loaded, as if it were a tape
drive.
-h Extract the actual directory, rather than the files that it
references. This prevents hierarchical restoration of complete
subtrees from the dump.
-m Extract by inode numbers rather than by file name. This is
useful if only a few files are being extracted, and one wants to
avoid regenerating the complete pathname to the file.
-N Do the extraction normally, but do not actually write any changes
to disk. This can be used to check the integrity of dump media
or other test purposes.
-s fileno
Read from the specified fileno on a multi-file tape. File
numbering starts at 1.
-u When creating certain types of files, restore may generate a
warning diagnostic if they already exist in the target directory.
To prevent this, the -u (unlink) flag causes restore to remove
old entries before attempting to create new ones. This flag is
recommended when using extended attributes to avoid improperly
an error. Always try to skip over the bad block(s) and continue.
ENVIRONMENT
TAPE Device from which to read backup.
TMPDIR Name of directory where temporary files are to be created.
FILES
/dev/sa0 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.
DIAGNOSTICS
The restore utility complains if it gets a read error. If -y has been
specified, or the user responds `y', restore will attempt to continue the
restore.
If a backup was made using more than one tape volume, restore will notify
the user when it is time to mount the next volume. If the -x or -i flag
has been specified, restore will also 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.
There are numerous consistency checks that can be listed by restore.
Most checks are self-explanatory or can ``never happen''. Common errors
are given below.
<filename>: not found on tape
The specified file name was listed in the tape directory, but was
not found on the tape. This is caused by tape read errors while
looking for the file, and from 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 when using a dump created on an active file system.
Incremental dump too low
When doing 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 incremental restore, a dump that does not begin its
coverage where 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, then its contents are probably partially wrong. If
an inode is being skipped or the tape is trying to resynchronize,
then no extracted files have been corrupted, though files may not
be found on the tape.
resync restore, skipped <num> blocks
After a dump read error, restore may have to resynchronize
The restore utility appeared in 4.2BSD.
BUGS
The restore utility can get confused when doing incremental restores from
dumps that were made on active file systems without the -L option (see
dump(8)).
A level zero dump must be done after a full restore. Because restore
runs in user code, it has no control over inode allocation; thus a full
dump must be done to get a new set of directories reflecting the new
inode numbering, even though the contents of the files is unchanged.
To do a network restore, you have to run restore as root. This is due to
the previous security history of dump and restore. (restore is written
to be setuid root, but we are not certain all bugs are gone from the
restore code - run setuid at your own risk.)
The temporary files /tmp/rstdir* and /tmp/rstmode* are generated with a
unique name based on the date of the dump and the process ID (see
mktemp(3)), except for when -r or -R is used. Because -R allows you to
restart a -r operation 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 should not conflict
with each other.
FreeBSD 14.0-RELEASE-p11 October 12, 2006 FreeBSD 14.0-RELEASE-p11