RESTORE(8) OpenBSD System Manager's Manual RESTORE(8)NAME
restore - restore files or file systems from backups made with dump
SYNOPSIS
restore [-chimRrtvxy] [-b blocksize] [-f file] [-s fileno] [file ...]
DESCRIPTION
The restore command 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. 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 works across networks, replacing the functionality of the old
rrestore program (though restore may still be invoked as rrestore). See
the -f option for more on reading backups from remote hosts.
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
files from a directory is to add the directory to the
extraction list and then delete those files that are
not needed.
extract All files on the extraction list are extracted from
the dump. restore will 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 Restore immediately 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 -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 List dump header information.
-R restore requests 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 changed
working directory 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 (not to mention the disk) if not used carefully.
An example:
# newfs /dev/rsd0g
# mount /dev/sd0g /mnt
# cd /mnt
# restore rf /dev/rst0
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.
restore, in conjunction with newfs(8) and dump(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 the entire content of the backup being
listed, unless the -h flag has been specified. Note that the -t
flag replaces the function of the old dumpdir 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, 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 block size dynamically.
-c Normally, restore will try to determine dynamically whether the
dump was made from an old (pre-4.4) or new format file system.
The -c flag disables this check, and only allows reading a dump
in the old format.
-f file
Read the backup from file; file may be a special device file like
/dev/rst0 (a tape drive), /dev/rsd1c (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).
-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.
-s fileno
Read from the specified fileno on a multi-file tape. File
numbering starts at 1.
-v Normally restore does its work silently. The -v (verbose) flag
causes it to type the name of each file it treats preceded by its
file type.
-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.
ENVIRONMENT
If the following environment variable exists it will be utilized by
restore:
TMPDIR The directory given in TMPDIR will be used instead of /tmp to
store temporary files. Refer to environ(7) for more information.
TAPE Default tape device to use instead of /dev/rst0.
FILES
/dev/rst0 the default tape drive
/dev/rst* raw SCSI tape interface
/tmp/rstdir* file containing directories on the tape
/tmp/rstmode* owner, mode, and time stamps for directories
./restoresymtable information passed between incremental restores
DIAGNOSTICS
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.
Converting to new file system format
A dump tape created from the old file system has been loaded. It
is automatically 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 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 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
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, its contents are probably partially wrong. If an
inode is being skipped or the tape is trying to resynchronize, 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
itself. This message lists the number of blocks that were
skipped over.
SEE ALSOenviron(7), dump(8), mount(8), newfs(8), rmt(8)HISTORY
The restore command appeared in 4.2BSD.
The 4.3BSD option syntax is implemented for backward compatibility but is
not documented here.
BUGS
restore can get confused when doing incremental restores from dumps that
were made on active file systems.
A level 0 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 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 process ID (see
mktemp(3)), except 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 shouldn't conflict with
each other.
OpenBSD 4.9 May 31, 2007 OpenBSD 4.9
