restore(1M)restore(1M)NAME
restore, rrestore - incremental filesystem restore
SYNOPSIS
restore key [ name ... ]
rrestore key [ name ... ]
DESCRIPTION
restore, and rrestore are applicable only to dumps made by dump(1m) from
EFS filesystems, but they can restore files into any type of filesystem,
not just an EFS filesystem.
restore reads tapes dumped with the dump(1M) command and restores them
relative to the current directory. Its actions are controlled by the key
argument. The key is a string of characters containing at most one
function letter and possibly one or more function modifiers. Any
arguments supplied for specific options are given as subsequent words on
the command line, in the same order as that of the options listed. 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 the entire tape. The tape is read and its full contents
loaded into the current directory. This should not be done lightly;
the r key should only be used to restore a complete level 0 dump
tape onto a clear filesystem or to restore an incremental dump tape
after a full level 0 restore. Thus
/etc/mkfs /dev/dsk/dks0d2s0
/etc/mount /dev/dsk0d2s0 /mnt
cd /mnt
restore r
is a typical sequence to restore a complete dump. Another restore
can be done to get an incremental dump in on top of this. 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 tape has been restored. Also, see
the note in the BUGS section below.
R Resume restoring. restore requests a particular tape of a multi
volume set on which to restart a full restore (see the r key above).
This allows restore to be interrupted and then restarted.
x The named files are extracted from the tape. If the named file
matches a directory whose contents had been written onto the tape,
and the h key is not specified, the directory is recursively
extracted. The owner, modification time, and mode are restored (if
Page 1
restore(1M)restore(1M)
possible). If no file argument is given, the root directory is
extracted, which results in the entire content of the tape being
extracted unless the h key has been specified.
t The names of the specified files are listed if they occur on the
tape. If no file argument is given, the root directory is listed,
which results in the entire content of the tape being listed unless
the h key has been specified. Note that the t key replaces the
function of the old dumpdir program.
i This mode allows interactive restoration of files from a dump tape.
After reading in the directory information from the tape, 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.
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.
cd arg Change the current working directory to the specified
argument.
pwd Print the full pathname of the current working directory.
add [arg] The current directory or specified argument is added to
the list of files to be extracted. If a directory is
specified, 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.
delete [arg]
The current directory or specified argument is deleted
from the list of files to be extracted. If a directory
is specified, 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 tape. restore asks 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.
Page 2
restore(1M)restore(1M)
setmodes All the directories that have been added to the
extraction list have their owner, modes, and times set;
nothing is extracted from the tape. 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.
help List a summary of the available commands.
quit restore immediately exits, even if the extraction list is
not empty.
The following characters can 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 tape
(in kilobytes). If the b option is not specified, restore tries to
determine the tape block size dynamically, but is only able to do so
if the block size is 32 or less. For larger sizes, the b option
must be used with restore.
f The next argument to restore is used as the name of the archive
instead of /dev/tape. If the name of the file is -, restore reads
from standard input. Thus, dump(1M) and restore can be used in a
pipeline to dump and restore a filesystem with the command
dump 0f - /usr | (cd /mnt; restore xf -)
If the name of the file is of the format machine:device, the
filesystem dump is restored from the specified machine over the
network. restore creates a remote server /etc/rmt, on the client
machine to access the tape device. Since restore is normally run by
root, the name of the local machine must appear in the .rhosts file
of the remote machine. If the filename argument is of the form
user@machine:device, restore attempts to execute as the specified
use on the remote machine. The specified user must have a .rhosts
file on the remote machine that allows root from the local machine.
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 does not ask whether it should abort the restore if gets a
tape error. It always tries to skip over the bad tape block(s) and
continue as best it can.
m restore extracts by inode numbers rather than by filename. This is
useful if only a few files are being extracted, and one wants to
avoid regenerating the complete pathname to the file.
Page 3
restore(1M)restore(1M)
h restore extracts the actual directory, rather than the files that it
references. This prevents hierarchical restoration of complete
subtrees from the tape.
s The next argument to restore is a number that selects the dump file
when there are multiple dump files on the same tape. File numbering
starts at 1.
n Only those files that are newer than the file specified by the next
argument are considered for restoration. restore looks at the
modification time of the specified file using the stat(2) system
call.
e No existing files are overwritten.
E Restores only non-existent files or newer versions (as determined by
the file status change time stored in the dump file) of existing
files. Note that the ls(1) command shows the modification time and
not the file status change time. See stat(2) for more details.
d Turn on debugging output.
o Normally restore does not use chown(2) to restore files to the
original user and group id unless it is being run by the superuser
(or with the effective user id of zero). This is to provide
Berkeley-style semantics. This can be overridden with the o option
which results in restore attempting to restore the original
ownership to the files.
N Do not write anything to the disk. This option can be used to
validate the tapes after a dump. If invoked with the r option,
restore goes through the motion of reading all the dump tapes
without actually writing anything to the disk.
DIAGNOSTICS
restore complains about bad key characters.
On getting a read error, restore prints out diagnostics. If y has been
specified, or the user responds y, restore attempts to continue the
restore.
If the dump extends over more than one tape, restore asks the user to
change tapes. If the x or i key has been specified, restore also asks
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.
Page 4
restore(1M)restore(1M)
Converting to new filesystem format.
A dump tape created from the old filesystem has been loaded. It is
automatically converted to the new filesystem format.
<filename>: not found on tape
The specified filename 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
filesystem.
expected next file <inumber>, got <inumber>
A file that was not listed in the directory showed up. This can
occur when using a dump tape created on an active filesystem.
Incremental tape too low
When doing incremental restore, a tape that was written before the
previous incremental tape, or that has too low an incremental level
has been loaded.
Incremental tape too high
When doing incremental restore, a tape that does not begin its
coverage where the previous incremental tape 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 read error has occurred. If a filename 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 tape read error, restore may have to resynchronize itself.
This message lists the number of blocks that were skipped over.
Error while writing to file /tmp/rstdir*
An error was encountered while writing to the temporary file
containing information about the directories on tape. Use the
TMPDIR environment variable to relocate this file in a directory
that has more space available.
Error while writing to file /tmp/rstdir*
An error was encountered while writing to the temporary file
containing information about the owner, mode and timestamp
information of directories. Use the TMPDIR environment variable to
relocate this file in a directory that has more space available.
EXAMPLES
restore r
Restores the entire tape into the current directory, reading from the
Page 5
restore(1M)restore(1M)
default tape device /dev/tape.
restore rf guest@kestrel.sgi.com:/dev/tape
Restores the entire tape into the current directory, reading from the
remote tape device /dev/tape on host kestrel.sgi.com using the guest
account.
restore x /etc/hosts /etc/fstab /etc/myfile
Restores the three specified files into the current directory, reading
from the default tape device /dev/tape.
restore x /dev/dsk
Restores the entire /dev/dsk directory and subdirectories recursively
into the current directory, reading from the default tape device
/dev/tape.
restore rN
Reads the entire tape and go through all the motions of restoring the
entire dump, without writing to the disk. This can be used to validate
the dump tape.
restore xe /usr/dir/foo
Restores (recursively) all files in the given directory /usr/dir/foo.
However, no existing files are overwritten.
restore xn /usr/dir/bar
Restores (recursively) all files that are newer than the given file
/usr/dir/bar.
FILES
/dev/tape This is the default tape device used unless the
environment variable TAPE is set.
/tmp/rstdir* This temporary file contains the directories on the tape.
If the environment variable TMPDIR is set, the file is
created in that directory.
/tmp/rstmode* This temporary file contains the owner, mode, and time
stamps for directories. If the environment variable
TMPDIR is set, the file is created in that directory.
./restoresymtable
Information is passed between incremental restores in
this file.
SEE ALSOdump(1M), mkfs(1M), mount(1M), rmt(1M), rhosts(4), mtio(7).
Page 6
restore(1M)restore(1M)NOTESrrestore is a link to restore.
BUGS
restore can get confused when doing incremental restores from dump tapes
that were made on active filesystems.
A level 0 dump must be done after a full restore. Because restore runs
in user code, it has no control over inode allocation. This results in
the files being restored having an inode numbering different from the
filesystem that was originally dumped. 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, so that later incremental
dumps will be correct.
Existing dangling symlinks are modified even if the e option is supplied,
if the dump tape contains a hard link by the same name.
Page 7
