UFSRESTORE(8) Maintenance Commands and Procedures UFSRESTORE(8)

NAME

ufsrestore - incremental file system restore

SYNOPSIS

/usr/sbin/ufsrestore i | r | R | t | x [abcdfhlmostvyLT]
[archive_file] [factor] [dumpfile] [n] [label]
[timeout] [filename]...

DESCRIPTION

The ufsrestore utility restores files from backup media created with
the ufsdump command. ufsrestores's actions are controlled by the key
argument. The key is exactly one function letter (i, r, R, t, or x)
and zero or more function modifiers (letters). The key string
contains no SPACE characters. Function modifier arguments are listed
on the command line in the same order as their corresponding function
modifiers appear in the key string.


filename arguments which appear on the command line, or as arguments
to an interactive command, are treated as shell glob patterns by the
x and t functions; any files or directories matching the patterns are
selected. The metacharacters *, ?, and [ ] must be protected from the
shell if they appear on the command line. There is no way to quote
these metacharacters to explicitly match them in a filename.


The temporary files rstdir* and rstmode* are placed in /tmp by
default. If the environment variable TMPDIR is defined with a non-
empty value, that location is used instead of /tmp.

OPTIONS

Function Letters

You must specify one (and only one) of the function letters listed
below. Note that i, x, and r are intended to restore files into an
empty directory. The R function is intended for restoring into a
populated directory.

i
Interactive. After reading in the directory information from the
media, ufsrestore invokes a shell-like interface that allows you
to browse through the dump file's directory hierarchy and select
individual files to be extracted. Restoration has the same
semantics as x (see below). See Interactive Commands, below, for
a description of available commands.


r
Recursive. Starting with an empty directory and a level 0 dump,
the r function recreates the filesystem relative to the current
working directory, exactly as it appeared when the dump was
made. Information used to restore incremental dumps on top of
the full dump (for example, restoresymtable) is also included.
Several ufsrestore runs are typical, one for each higher level
of dump (0, 1, ..., 9). Files that were deleted between the
level 0 and a subsequent incremental dump will not exist after
the final restore. To completely restore a file system, use the
r function restore the level 0 dump, and again for each
incremental dump. Although this function letter is intended for
a complete restore onto a new file system (one just created with
newfs(8)), if the file system contains files not on the backup
media, they are preserved.


R
Resume restoring. If an r-mode ufsrestore was interrupted, this
function prompts for the volume from which to resume restoring
and continues the restoration from where it was left off.
Otherwise identical to r.


t
Table of contents. List each filename that appears on the media.
If no filename argument is given, the root directory is listed.
This results in a list of all files on the media, unless the h
function modifier is in effect. The table of contents is taken
from the media or from the specified archive file, when the a
function modifier is used. The a function modifier is mutually
exclusive with the x and r function letters.


x
Extract the named files from the media. Files are restored to
the same relative locations that they had in the original file
system.

If the filename argument matches a directory whose contents were
written onto the media, and the h modifier is not in effect, the
directory is recursively extracted, relative to the current
directory, which is expected to be empty. For each file, the
owner, modification time, and mode are restored (if possible).

If you omit the filename argument or specify ., the root
directory is extracted. This results in the entire tape being
extracted, unless the h modifier is in effect. . With the x
function, existing files are overwritten and ufsrestore displays
the names of the overwritten files. Overwriting a currently-
running executable can have unfortunate consequences.

Use the x option to restore partial file system dumps, as they
are (by definition) not entire file systems.

Function Modifiers

a archive_file
Read the table of contents from archive_file
instead of the media. This function modifier can
be used in combination with the t, i, or x
function letters, making it possible to check
whether files are on the media without having to
mount the media. When used with the x and
interactive (i) function letters, it prompts for
the volume containing the file(s) before
extracting them.


b factor
Blocking factor. Specify the blocking factor for
tape reads. For variable length SCSI tape devices,
unless the data was written with the default
blocking factor, a blocking factor at least as
great as that used to write the tape must be used;
otherwise, an error will be generated. Note that a
tape block is 512 bytes. Refer to the man page for
your specific tape driver for the maximum blocking
factor.


c
Convert the contents of the media in 4.1BSD format
to the new ufs file system format.


d
Debug. Turn on debugging output.


f dump_file
Use dump_file instead of /dev/rmt/0 as the file to
restore from. Typically dump_file specifies a
tape or diskette drive. If dump_file is specified
as `-', ufsrestore reads from the standard input.
This allows ufsdump(8) and ufsrestore to be used
in a pipeline to copy a file system:

example# ufsdump 0f - /dev/rdsk/c0t0d0s7 \
| (cd /home;ufsrestore xf -)


If the name of the file is of the form
machine:device, the restore is done from the
specified machine over the network using rmt(8).
Since ufsrestore is normally run by root, the name
of the local machine must appear in the /.rhosts
file of the remote machine. If the file is
specified as user@machine:device, ufsrestore will
attempt to execute as the specified user on the
remote machine. The specified user must have a
.rhosts file on the remote machine that allows the
user invoking the command from the local machine
to access the remote machine.


h
Extract or list the actual directory, rather than
the files that it references. This prevents
hierarchical restoration of complete subtrees from
the tape.


l
Autoload. When the end-of-tape is reached before
the restore is complete, take the drive off-line
and wait up to two minutes (the default, see the T
function modifier) for the tape drive to be ready
again. This gives autoloading (stackloader) tape
drives a chance to load a new tape. If the drive
is ready within two minutes, continue. If it is
not, prompt for another tape and wait.


L label
The label that should appear in the header of the
dump file. If the labels do not match, ufsrestore
issues a diagnostic and exits. The tape label is
specific to the ufsdump tape format, and bears no
resemblance to IBM or ANSI-standard tape labels.


m
Extract by inode numbers rather than by filename
to avoid regenerating complete pathnames.
Regardless of where the files are located in the
dump hierarchy, they are restored into the current
directory and renamed with their inode number.
This is useful if only a few files are being
extracted.


o
Offline. Take the drive off-line when the restore
is complete or the end-of-media is reached and
rewind the tape, or eject the diskette. In the
case of some autoloading 8mm drives, the tape is
removed from the drive automatically.


s n
Skip to the nth file when there are multiple dump
files on the same tape. For example, the command:

example# ufsrestore xfs /dev/rmt/0hn 5


would position you to the fifth file on the tape
when reading volume 1 of the dump. If a dump
extends over more than one volume, all volumes
except the first are assumed to start at position
0, no matter what "s n" value is specified.

If "s n" is specified, the backup media must be at
BOT (beginning of tape). Otherwise, the initial
positioning to read the table of contents will
fail, as it is performed by skipping the tape
forward n-1 files rather than by using absolute
positioning. This is because on some devices
absolute positioning is very time consuming.


T timeout [hms]
Sets the amount of time to wait for an autoload
command to complete. This function modifier is
ignored unless the l function modifier has also
been specified. The default timeout period is two
minutes. The time units may be specified as a
trailing h (hours), m (minutes), or s (seconds).
The default unit is minutes.


v
Verbose. ufsrestore displays the name and inode
number of each file it restores, preceded by its
file type.


y
Do not ask whether to abort the restore in the
event of tape errors. ufsrestore tries to skip
over the bad tape block(s) and continue as best it
can.

Interactive Commands

ufsrestore enters interactive mode when invoked with the i function
letters. Interactive commands are reminiscent of the shell. For those
commands that accept an argument, the default is the current
directory. The interactive options are:

add [filename]
Add the named file or directory to the list of
files to extract. If a directory is specified,
add that directory and its files (recursively)
to the extraction list (unless the h modifier
is in effect).


cd directory
Change to directory (within the dump file).


delete [filename]
Delete the current directory, or the named file
or directory from the list of files to extract.
If a directory is specified, delete that
directory and all its descendents from the
extraction list (unless the h modifier is in
effect). The most expedient way to extract a
majority of files from a directory is to add
that directory to the extraction list, and then
delete specific files to omit.


extract
Extract all files on the extraction list from
the dump media. ufsrestore asks which volume
the user wishes to mount. The fastest way to
extract a small number of files is to start
with the last volume and work toward the first.
If "s n" is given on the command line, volume 1
will automatically be positioned to file n when
it is read.


help
Display a summary of the available commands.


ls [directory]
List files in directory or the current
directory, represented by a `.' (period).
Directories are appended with a `/' (slash).
Entries marked for extraction are prefixed with
a `*' (asterisk). If the verbose option is in
effect, inode numbers are also listed.


marked [directory]
Like ls, except only files marked for
extraction are listed.


pager
Toggle the pagination of the output from the ls
and marked commands. The pager used is that
defined by the PAGER environment variable, or
more(1) if that envar is not defined. The PAGER
envar may include white-space-separated
arguments for the pagination program.


pwd
Print the full pathname of the current working
directory.


quit
ufsrestore exits immediately, even if the
extraction list is not empty.


setmodes
Prompts: set owner/mode for `.' (period). Type
y for yes to set the mode (permissions, owner,
times) of the current directory `.' (period)
into which files are being restored equal to
the mode of the root directory of the file
system from which they were dumped. Normally,
this is what you want when restoring a whole
file system, or restoring individual files into
the same locations from which they were dumped.
Type n for no, to leave the mode of the current
directory unchanged. Normally, this is what you
want when restoring part of a dump to a
directory other than the one from which the
files were dumped.


setpager command
Sets the command to use for paginating output
instead of the default or that inherited from
the environment. The command string may include
arguments in addition to the command itself.


verbose
Toggle the status of the v modifier. While v is
in effect, the ls command lists the inode
numbers of all entries, and ufsrestore displays
information about each file as it is extracted.


what
Display the dump header on the media.

OPERANDS

The following operands are supported.

filename
Specifies the pathname of files (or directories) to be
restored to disk. Unless the h function modifier is also
used, a directory name refers to the files it contains,
and (recursively) its subdirectories and the files they
contain. filename is associated with either the x or t
function letters, and must come last.

USAGE

See largefile(7) for the description of the behavior of ufsrestore
when encountering files greater than or equal to 2 Gbyte (2^31
bytes).

EXIT STATUS

The following exit values are returned:

0
Successful completion.


1
An error occurred. Verbose messages are displayed.

ENVIRONMENT VARIABLES

PAGER
The command to use as a filter for paginating output. This
can also be used to specify the options to be used. Default
is more(1).


TMPDIR
Selects the directory for temporary files. Defaults to /tmp
if not defined in the environment.

FILES

/dev/rmt/0
the default tape drive


$TMPDIR/rstdir*
file containing directories on the tape


$TMPDIR/rstmode*
owner, mode, and timestamps for directories


./restoresymtable
information passed between incremental
restores

SEE ALSO

more(1), ufsdump(5), attributes(7), largefile(7), mkfs(8), mount(8),
rmt(8), ufsdump(8)

DIAGNOSTICS

ufsrestore complains about bad option characters.


Read errors result in complaints. If y has been specified, or the
user responds y, ufsrestore will attempt to continue.


If the dump extends over more than one tape, ufsrestore asks the user
to change tapes. If the x or i function letter has been specified,
ufsrestore also asks which volume the user wishes to mount. If the s
modifier has been specified, and volume 1 is mounted, it is
automatically positioned to the indicated file.


There are numerous consistency checks that can be listed by
ufsrestore. 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, using a dump tape created on an active file
system, or restoring a partial dump with the r function.


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 file system.


Incremental tape too low

When doing an 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 one
that has too high an incremental level has been loaded.


media read error: invalid argument

Blocking factor specified for read is smaller than the blocking
factor used to write data.


Tape read error while restoring
Tape read error while skipping over inode inumber
Tape read error while trying to resynchronize
A tape 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 ufsrestore, skipped num

After a tape read error, ufsrestore may have to resynchronize
itself. This message lists the number of blocks that were
skipped over.


Incorrect tape label. Expected `foo', got `bar'.

The L option was specified, and its value did not match what was
recorded in the header of the dump file.

NOTES

ufsrestore can get confused when doing incremental restores from dump
tapes that were made on active file systems.


A level 0 dump must be done after a full restore. Because ufsrestore
runs in user mode, it has no control over inode allocation. This
means that ufsrestore repositions the files, although it does not
change their contents. Thus, a full dump must be done to get a new
set of directories reflecting the new file positions, so that later
incremental dumps will be correct.

February 17, 2023 UFSRESTORE(8)