RESTORE(8) 386BSD System Manager's Manual RESTORE(8)
NAME
restore - restore files or file systems from backups made with dump
SYNOPSIS
restore key [name ...]
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. Restore cannot work across a
network, to do this, see the companion command rrestore. The actions of
restore are controlled by the given key, which is a string of characters
containing at most one function letter and possibly one or more function
modifiers. Other arguments to the command are file or directory names
specifying the files that are to be restored. Unless the h key is
specified (see below), the appearance of a directory name refers to the
files and (recursively) subdirectories of that directory.
The function portion of the key is specified by one of the following
letters:
r Restore (rebuild a file system). The target file system should
be made pristine with newfs(8), mounted and the user cd'd into
the pristine file system before starting the restoration of the
initial level 0 backup. If the level 0 restores successfully, the
r key may be used to restore any necessary incremental backups on
top of the level 0. The r key precludes an interactive file
extraction and can be detrimental to ones health if not used
carefully (not to mention the disk). An example:
newfs /dev/rrp0g eagle
mount /dev/rp0g /mnt
cd /mnt
restore rf /dev/rst8
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.
R Restore requests a particular tape of a multi volume set on which
to restart a full restore (see the r key above). This is useful
if the restore has been interrupted.
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
key 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 key has been specified.
t The names of the specified files are listed if they occur on the
backup. If no file argument is given, then the root directory is
listed, which results in the entire content of the backup being
listed, unless the h key has been specified. Note that the t key
replaces the function of the old dumpdir(8) program.
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 key 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 key 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 the files that are 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 key 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 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 key is toggled. When set, the
verbose key 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.
The following characters may be used in addition to the letter that
selects the function desired.
b The next argument to restore is used as the block size of the
media (in kilobytes). If the -b option is not specified, restore
tries to determine the media block size dynamically.
f The next argument to restore is used as the name of the archive
instead of /dev/rmt?. If the name of the file is `-', restore
reads from standard input. Thus, dump(8) and restore can be used
in a pipeline to dump and restore a file system with the command
dump 0f - /usr | (cd /mnt; restore xf -)
h Restore extracts the actual directory, rather than the files that
it references. This prevents hierarchical restoration of
complete subtrees from the dump.
m Restore will 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 The next argument to restore is a number which selects the file
on a multi-file dump tape. File numbering starts at 1.
v Normally restore does its work silently. The v (verbose) key
causes it to type the name of each file it treats preceded by its
file type.
y Restore will not ask whether it should abort the restore if gets
an error. It will always try to skip over the bad block(s) and
continue as best it can.
DIAGNOSTICS
Complaints about bad key characters.
Complaints 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 key 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 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
itself. This message lists the number of blocks that were
skipped over.
FILES
/dev/rmt? 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.
SEE ALSO
rrestore(8) dump(8), newfs(8), mount(8), mkfs(8)
BUGS
Restore can get confused when doing incremental restores from dump that
were made on active file systems.
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
restore must be done to get a new set of directories reflecting the new
inode numbering, even though the contents of the files is unchanged.
HISTORY
The restore command appeared in 4.2BSD.
4th Berkeley Distribution July 23, 1991 4