WBAK(1) Domain/OS BSD WBAK(1)
NAME
wbak - create a magnetic media backup file
SYNOPSIS
wbak -f fileno [-dev | m[unit] | f | ct]
[-full|-incr|-af dtm|-bef dtm]
[-fid id] [-own id] [-vid vol_id]
[-sla|-nsla] [-wla|-nwla] [-nhi] [-pdtu]
[-reo] [-reten|-nreten] [-no_eot]
[-sysboot] [-l|-ld|-lf|-ll] [-to filename]
[-type uasc|unstruct|hdru]
[-r] [-stdout] [-presr10] pathname...
DESCRIPTION
wbak writes one or more objects to either a removable media, disk
file or standard output. These objects may be directory trees, files, or
links. For each object, the information saved includes the name, object
data, and attributes associated with the object, such as the access
control list. This lets you reconstruct files, the directory tree, or any
portion of the tree using the rbak command.
The wbak and rbak commands are intended both for disk backup and for
interchanging information between separate Domain installations. Use the
rwmt command to read and write magnetic media that are used for
interchanging information with non-Domain installations.
pathname (required)
Specify the name of the object to be written to backup
media. This may be a directory, file, or link. If it is
a file, then the file is written as specified. If it is a
link, then the link is resolved and the resolution object
is written to backup media. If it is a directory, all
subordinate files and subdirectories in the tree are
written. Note that the pathname specified reflects the way
the directory is stored on the backup media, and that the
same name must be used when reading files using pathnames
in rbak. Multiple pathnames and wildcarding are
permitted. If you omit this argument, wbak will prompt
you for it. You may specify a hyphen (-) as an argument
to direct wbak to standard input for further arguments and
options.
OPTIONS
The -f option is required, as it specifies where on the backup media the
new file is to be written. If you omit it, wbak will prompt you for it.
Tape File Identifiers
-fid file_id Specify a 1-17 character file ID to be written in the file
header label for use when writing a file to a labeled
volume. If this option is omitted, the file is not named
and can only be restored by the file number.
-f [position] Specify the file position for the write operation. Valid
values for position are cur, end, or a nonzero integer. A
position of cur specifies that the file should be written
at the current position on the backup media; the media
must have been previously written by wbak and its position
must not have been disturbed.
A position of end specifies that the file should be
written at the end of the backup media file set. This
causes wbak to append the specified disk file (pathname
argument) to the very end of the file set.
A position specified by a nonzero integer value causes the
file to be written at that absolute position in the backup
media volume. If multiple pathname arguments are
supplied, the value of position is incremented by one
after each file has been written.
The default value for position is 1.
Mode Control
The object specified by the pathname argument must be a directory for
either -full or -incr to have meaning.
-full (default)
Specify a full backup; save all files in specified trees.
-incr Specify an incremental backup; save files that were
modified since the last backup recorded in the
backup_history file stored in the pathname directory.
-af dtm Save all files modified after the given date and time; dtm
is in the form "yy/mm/dd.hh:mm". The date defaults to
today, and the time to midnight if either of those are
omitted from dtm.
-bef dtm Save all files last modified before the given date and
time.
Label Control
-wla (default) Write the backup media volume label if the backup file
number is 1.
-nwla Suppress writing of the backup media volume label.
-own id Specify backup media volume owner (1-14 character name).
This option is only meaningful when used with the -wla
option.
-vid vol_id Specify a 1-6 character volume ID for use when labeling a
volume. This option is only meaningful when the backup
file number is 1. The default volume ID is ' ' (blank).
-sla (default) Display the label information written for this backup file
on standard output.
-nsla Suppress output of label information.
Listing Control
You may include the -l option, or any combination of -ld, -lf, and -ll.
-l Write the names of all files, directories, and links saved
to standard output.
-lf Write the names of all files saved to standard output.
-ld Write the names of all directories saved to standard
output.
-ll Write the names of all links saved to standard output.
Backup Device Control
-dev d[unit] Specify device type and unit number. d must be either m
(for reel-to-reel magnetic tape), ct (for cartridge tape),
or f (for floppy), depending on which drive is being used.
unit is an integer (0-3). Both are required for
reel-to-reel tapes (that is, -dev m2). A unit number is
not required for floppy disks and cartridge tapes (that
is, -dev f/f1). If this option is omitted, rbak assumes
device m0.
CAUTION: Floppy disk support for this command is
limited. In particular, error detection
during reads and writes is poor. do not
use this command with floppy disks when the
data being placed on the floppy disks are
critical and unrecoverable.
-to filename Backup output is written to the specified streams object
rather than removable media. This can then be restored
using the -from option in rbak. If the file already
exists, use the -r option to replace it. If -type option
is not specified the file will be assigned the default
type. You cannot use the -file n option with streams.
-type [uasc | unstruct | hdru]
Specify the type of the object filename. It can be one of
ASCII (uasc), Unstructured (unstruct) or Streams header-
undefined (hdru) type.
-r If the object specified with the -to option already
exists, this option allows it to be replaced. The type of
filename is however left unchanged.
-stdout The backup output is written to standard output.
-reo Force previous backup media volume to be reopened, and
suppress reading of backup media volume label. Use only
when backup media has not been repositioned since last
wbak or rbak.
Special Cartridge Tape Control Options
-reten Retension the cartridge tape (unwind to the end, then
rewind). This can be helpful if you have encountered
cartridge tape reading errors. Retensioning requires
about 1.5 minutes to complete.
-nreten (default)
Do not retension the cartridge tape.
-no_eot Suppress the writing of two tape marks at the end of the
tape file, which are the standard signal for end of tape.
The cartridge can't position between the two tapemarks to
be ready for a successive call to wbak (as it does on
magtape), without rewinding the tape and searching
forward, so this option speeds up multiple invocations of
wbak. It should not be used on the last invocation of
wbak. Also, -f cur should be used on all wbak invocations
in a series except the first one.
-sysboot Permit use of a bootable tape that has a special boot
program at the beginning. This option causes wbak to skip
over the first file on the tape. This option is only
necessary when the first file on the tape is being written
(-f 1).
Miscellaneous Control Options
-nhi Suppress update of the backup history file.
- (hyphen) Read standard input for further arguments or options;
input is accepted until wbak receives an EOF.
-pdtu Preserves the last date/time-used information on objects.
After each object is backed up on tape, the date/time-used
information is reset to the value it had before the
backup.
-presr10 Allows you to make a tape with pre-SR10 format from an
SR10 node. This tape will have no ACLs by default. You
can restore it to a pre-SR10 volume by means of the pre-
SR10 rbak. If you make a tape without this option it will
not be readable on a pre-SR10 system.
EXAMPLES
$ wbak //mask/wby -f 1 -af 87/11/19.12.00 -fid wby -L
This command writes the directory //mask/wby to tape. The directory is
written out to tape file one, and the file ID wby is written to the
file's label. Disk files from directory wby are written to the tape only
if they have been modified since noon on November 19, 1987. The label
and the names of the files written to tape are printed to standard
output.
When this command is executed, wbak writes the following information to
standard output:
Label:
File number: 1
File section: 1
File id: wby
Date written: 1987/ll/20 10:47:58 EST
Starting write:
(file) "//mask/wby/among" written
(file) "//mask/wby/school" written
(file) "//mask/wby/children" written
(file) "//mask/wby/backup_history" written
(dir) "//mask/wby/" written.
Write complete.
This command backs up the entire contents of the node whose entry
directory name is gooey. Note that the file ID is specified as "node 27
backup" to make it easy to identify when you want to reload it, and that
the command assigns volume and owner IDs.
$ wbak -f 1 -own "john doe" -vid "volbk2" -fid "node 27 backup" //gooey
When this command is executed, wbak writes the following information to
standard output:
Label:
Volume id: VOLBK2
Owner id: john doe
File number: 1
File section: 1
File id: n 27 backup
File written: 1987/02/17 18:00:39 EST
Starting write:
Write complete.
This command uses wildcards to match only those files in the ug
subdirectory of the current working directory whose names begin with the
letters a through f and end with _example.
$ wbak -f 1 -own "john doe" -vid "volbk1" ug/[a-f*]_example -l
When this command is executed, wbak writes the following information to
standard output:
Label:
Volume id: VOLBK1
Owner id: john doe
File number: 1
File section: 1
File id: (no id specified)
File written: 1988/02/17 17:58:52 EST
Starting write:
(file) "ug/cmf_example" written.
(file) "ug/cmt_example" written.
(file) "ug/cpboot_example" written.
(file) "ug/cpf_example" written.
(file) "ug/cpt_example" written.
(file) "ug/fpat_example" written.
(file) "ug/fppmask_example" written.
(file) "ug/fst_example" written.
Write complete.
$ wbak src -to /backup/bck_out.file
This command writes the backup output for the directory src to the file
/fred/bck_out.file. The directory can be restored in either of the
following two ways :
rbak src -from /backup/bck_out.file
OR
cat /fred/bck_out.file | rbak src -stdin
Using streams as a backup output media, it is possible to stage the
backup output to intermediate disks and then use rwmt to write the
intermediate file to the magnetic tape. The sequence to use is as follows
$ wbak //otter -to //backup/ot
wbak //otter -to //backup/tmp1
This writes the backup output to an intermediate file //backup/tmp1
followed by
rwmt -f 2 -w //backup/tmp1 -raw -rl 8192 -nobs -ansi
When the magtape unit is available at a later time the intermediate file
is written to the magtape. Note that it is ESSENTIAL to use the -raw, -rl
8192 and the -nobs options of rwmt, for rbak to be able to read the
backup from tape. All tapes used for this must must have the ANSI
speified volume label. You can only use this sequence for magnetic
tapes. rbak will not be able to restore data written using the above
sequence for cartridge tapes instead of magnetic tapes. This
sequence has exactly the same effect as using
wbak //otter -dev mt -f 2
You can then use rbak as follows to retrieve the data
rbak //otter -f 2 -dev mt
SEE ALSO
rbak(1), rwmt(1)