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)