vxrestore(1M)vxrestore(1M)NAME
vxrestore, rvxrestore - restore file system incrementally, local or
across network
SYNOPSIS
blocksize] opt] file] number] [filename ...]
blocksize] opt] file] number] [filename ...]
key [filename ...]
key [filename ...]
DESCRIPTION
and read tapes previously dumped by the or command (see vxdump(1M)).
restores from tape on the local system; restores from tape on a remote
system. runs on the remote machine to access the tape device.
and support both getopt(3C) and traditional command line invocations as
shown above. The original command line style is supported for compati‐
bility with previous versions of and for synonymy with the existing
program used for hfs file systems.
For the original command line style, actions taken are controlled by
the key argument where key is a string of characters containing exactly
one function letter from the group and zero or more function modifiers
from the group One or more filename arguments, if present, are file or
directory names specifying the files to restore. Unless the modifier
is specified (see below), the appearance of a directory name refers to
the files and (recursively) subdirectories of that directory.
is the default legacy DSF tape device, and is the default persistent
DSF tape device.
Options
recognizes the following options:
Allow interactive restoration of files from a dump tape.
After reading the directory information from the tape,
provides a shell-like interface that lets you move around
the directory tree selecting files to extract. The avail‐
able commands are listed below. For commands that require
an argument, the default is the current directory.
Add the current directory or specified argument
to the list of files to extract. If a
directory is specified, the directory and
all its descendents are added to the
extraction list (unless the key is speci‐
fied on the command line). File names on
the extraction list are displayed with a
leading when listed by
Change the current working directory to the specified
argument.
Delete the current directory or specified argument
from the list of files to extract. If a
directory is specified, the directory and
all its descendents are deleted from the
extraction list (unless is specified on the
command line). The best way to extract
most files from a directory is to add the
directory to the extraction list, then
delete unnecessary files.
Extract all files named on the extraction list
from the dump tape. prompts for the volume
to mount. The fastest way to extract a few
files is to start with the last volume,
then work toward the first volume.
List a summary of the available commands.
List the current or specified directory.
Entries that are directories are displayed
with a trailing Entries marked for extrac‐
tion are displayed with a leading If the
verbose key is specified, the inode number
of each entry is also listed.
Print the full pathname of the current working directory.
immediately exits, even if the extraction list is not
empty.
(control-D) is a synonym for
Set the owner, modes, and times of all directories
that are added to the extraction list.
Nothing is extracted from the tape. This
setting is useful for cleaning up after a
restore aborts prematurely.
The sense of the
modifier is toggled. When set to verbose,
the command lists the inode numbers of all
entries. and prints information about each
file as it is extracted.
Read the tape and load into the current directory.
Be careful when using the option. Restore only a complete
dump tape onto a clear file system, or restore an incre‐
mental dump tape after a full level zero restore. The
following is a typical sequence to restore a complete
dump:
The following is a typical sequence to restore a complete
dump if you are using the VERITAS Volume Manager:
You can then execute another to restore an incremental
dump on top of this. Note that leaves a file, in the root
directory of the file system to pass information between
incremental passes. Remove this file when the last incre‐
mental tape is restored.
Resume a full restore.
restarts from a checkpoint it created during a full
restore (see above). It requests a particular tape of a
multi-volume set on which to restart a full restore. This
provides a means for interrupting and restarting a multi-
volume
number
is the dump file number to recover. This is useful if
there is more than one dump file on a tape.
Names of
filenames, as specified on the command line, are listed if
they occur on the tape. If no filename is given, the root
directory is listed, which results in the entire content
of the tape being listed, unless is specified.
Extract named files from the tape.
If the named file matches a directory whose contents are
written onto the tape, and the option is not specified,
the directory is recursively extracted. The owner, modi‐
fication time, and mode are restored (if possible). If no
filename argument is given, the root directory is
extracted, which results in the entire contents of the
tape being extracted, unless is specified.
The following options can be used in addition to the letter that
selects the primary function:
Specify the block size of the tape in kilobytes.
If the option is not specified, determines the tape block
size dynamically. (This option exists to preserve back‐
wards compatibility with previous versions of
By default,
writes data directly to disk and does not use the system
buffer cache to restore data. This ensures that the buf‐
fer cache does not change on an operational system, which
generally improves system performance. Writing data syn‐
chronously to disk may, however, slightly slow the restore
process. If you specify the option, will cache data
before writing to disk. This preserves compatibility with
previous versions of
Specify how to handle a
vxfs file that has extent attribute information. Extent
attributes include reserved space, a fixed extent size,
and extent alignment. It may not be possible to preserve
the information if the destination file system does not
support extent attributes, has a different block size than
the source file system, or lacks free extents appropriate
to satisfy the extent attribute requirements. Valid val‐
ues for opt are:
Fail to restore the file if extent attribute information
cannot be kept.
Ignore extent attribute information entirely.
Issue a warning message if extent attribute information
cannot be kept
(the default).
Specify the name of the archive instead
of or If the name of the file is reads from standard
input. So you can use and in a pipeline to vxdump and
vxrestore a file system with the command
You can use an archive name of the form to specify a tape
device on a remote machine.
Extract the actual directory,
rather than the files to which it refers. This prevents
hierarchical restoration of complete subtrees.
Extract by inode numbers rather than by file name.
This is useful if only a few files are being extracted and
you want to avoid regenerating the complete pathname to
the file.
Specify verbose output;
list the name of each file restored, preceded by its file
type.
Do not ask whether to abort the operation if
encounters a tape error, but continue. Normally asks
whether to continue after encountering a read error. With
this option, continues without asking, skipping over the
bad tape block(s) and continuing as best it can.
Operands
recognizes the following operands:
filename
The name one or more files that contain file or directory
names specifying the files to restore.
key A string of characters controlling what actions are taken
by This string contains exactly one function letter from
the group and zero or more function modifiers from the
group
Compatibility
A file with a large uid (user ID of the file owner) or large gid (group
ID of the file owner) cannot be restored correctly on a file system
that does not support large IDs. Instead, the owner and/or group of
the file will be that of the user invoking (A large ID is a value
greater than 65535. The VxFS Version 2 disk layout does not support
large IDs).
Notes
If the dump tape contains files larger than 2 gigabytes, and if the
file system being restored to does not support files larger than 2
gigabytes, the file is not restored correctly. Instead it is truncated
to 2 gigabytes.
The current version of can read dumps produced by older versions of
Dumps produced by on other platforms can also be read by provided they
are not from a version of more recent the version of in use.
can restore files to a file system of a type other than VxFS. If the
file system type does not support extent attributes, than the extent
attributes are not restored (see the option).
A version of resides in for use when the system is in single user
state.
DIAGNOSTICS
complains if a read error is encountered. If the option has been spec‐
ified, or you respond tries to continue the restore.
If the dump extends over more than one tape, asks the user to change
tapes. If the or option has been specified, also asks which volume 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 vxrestore can list. Besides
media errors, other problems that can interrupt a restore include per‐
mission inconsistencies, resource unavailability, or inconsistencies
encountered on the media that are the result of incorrect dump proce‐
dures.
Error Processing
vxrestore typically terminates if it encounters an error condition
severe enough that it cannot continue reliably. Termination generally
indicates that there is a serious problems either in the backup media
or in the administrative procedures used during the dump/restore.
You can override a termination in interactive mode or by specifying the
option when you invoke If a termination is overridden, tries to skip
over bad data and continue restoring. It is not a good practice to do
this except under extraordinary circumstances. As part of normal
dump/restore processing, it is best to identify the underlying cause of
the problem and repair it.
Error Conditions
Error conditions that can terminate a restore can be grouped into the
following general categories:
· media problems
· resource or permission problems
· consistency check failures
A media error can occur while accessing the dump/restore media, or may
be caused by selecting an incorrect volume for restore processing.
Also check for physical problems such as damage to the tape, and be
sure that the tape drive is cleaned. Some typical media problem error
messages are:
A resource allocation or permission problem can occur while trying to
allocate or access files or memory space required by for its internal
processing. To avoid some common problems, be sure you are running
with the correct UID, that target files have write permission, and that
there is sufficient memory. Some typical resource allocation or per‐
mission error messages are:
A consistency check failure generally occurs while examining the data
on the dump/restore media. This kind of problem may be caused by a
media failure, by dumping a mounted and active file system, or because
of an error in media or parameter selection. Some typical consistency
check failure error messages are:
There are numerous consistency checks that can list. Most checks are
self-explanatory or rarely occur. Here are some common errors:
The specified file name was listed in the tape directory
but 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.
A file not listed in the directory appeared.
This can occur when using a dump tape created on an
active file system. Dumps should be performed with the
file system unmounted or the system in single-user mode
(see init(1M)) to insure a consistent dump. If the HP
OnLineJFS product is installed, the dump can be performed
in the multi-user environment using a snapshot file sys‐
tem with the online backup facility (see the option of
mount_vxfs(1M)).
When doing an incremental restore,
a tape that was written before the previous incremental
tape, or that has too low an incremental level was
loaded.
Note: if this error occurs, you are either restoring
tapes out of order or restoring from a dump file that was
created using the option to At this point, displays a
warning message and asks if you want to continue doing
the restore. Respond with only if you are sure that you
are restoring from a dump file created using the option.
Enter to abort the restore.
When doing an incremental restore,
a tape that does not begin its coverage where the previ‐
ous incremental tape left off, or that has too high an
incremental level was loaded.
Note:
If this error occurs, you are either restoring tapes out
of order or restoring from a dump file that was created
using the option to At this point displays a warning mes‐
sage and asks if you want to continue doing the restore.
Respond with only if you are sure that you are restoring
from a dump file created using the option. Enter to
abort the restore.
A tape-read error occurred.
If a file name is specified,
the contents of the restored
files may be incorrect. If
is skipping an inode or is
trying to resynchronize the
tape, no extracted files are
corrupted, although files may
not be found on the tape.
After a tape-read error,
may have to resynchronize
itself. This message indi‐
cates the number of blocks
skipped over. This message
will also be generated by
older versions of while skip‐
ping over files larger than 2
gigabytes dumped by a more
recent version of
WARNINGS
can get confused when doing incremental
restores from dump tapes that were made on
active file systems.
A level 0 dump (see the vxdump(1M) manual
page) must be done after a full restore.
Because runs in user code, it has no con‐
trol over inode allocation; thus a full
dump must be done to get a new set of
directories reflecting the new inode num‐
bering, even though the contents of the
files are unchanged.
does not restore access control lists
(ACLs).
AUTHOR
and are based on the program distributed in
the 4.4 Berkeley Software Distribution,
developed by the the University of Califor‐
nia, Berkeley, and its contributors.
FILES
default legacy DSF tape drive
default persistent DSF tape drive
file containing directories on the tape
owner, mode, and time stamps for directo‐
ries
information passed between incremental
restores
SEE ALSOls(1), extendfs_vxfs(1M), fsadm_vxfs(1M),
init(1M), mkfs(1M), mkfs_vxfs(1M),
mount(1M), mount_vxfs(1M), newfs_vxfs(1M),
restore(1M), rmt(1M), vxdump(1M),
getopt(3C).
vxrestore(1M)
