10.0;rbak (read_backup), revision 1.0, 88/03/04
rbak (read_backup) -- Restore or index a magnetic media backup file.
usage: rbak {-f fileno|-fid id} [-dev | m[unit] | f | ct]
[-int|-index] [-sla|-nsla] [-anys] [-reo] [-pr pn]
[-cr|-r|-ms|-md] [-force] [-du] [-l|-ld|-lf|-ll]
[-reten|-nreten] [-rew] [-dacl|-sacl] [-unl]
[-pdt] [-stdin] {{-all|pn} [-as disk_pn]}...
DESCRIPTION
rbak restores objects from the backup input media written by wbak
(write_backup). The backup input media can be one of magnetic media,
file or standard input.
Use wbak and rbak to back up disks and to transfer information between
separate Domain installations. (Use the rwmt (read_write_magtape) command
to transfer information to and from non-Domain installations.)
rbak operates in either index or interchange mode. To restore objects to
disk, use interchange mode (-int). To list object names on standard
output, without restoring any information to disk, use index mode
(-index).
pathname (optional)
Specify name of the object to be indexed or restored to
disk. This may be a directory, file, or link. If the
object is being restored, the new disk object has the same
name. If you wish the disk file to be saved under a
different name, use -as (below). Multiple pathnames are
permitted; however, wildcarding is not supported.
Default if omitted: must use -all
OPTIONS
Backup File Identifiers
One of the following options is required.
-f file_no Reads the back up file with the file number specified.
You assigned this number with wbak.
-f cur Begins reading at current position on the back up medium.
-fid file_id Reads the back up filename specified. You assigned this
name using wbak.
-int (default) Selects interchange mode. Backup files are restored to
disk.
-index Selects index mode. Backup filenames are listed on
standard output; no information is restored to disk.
Catalog Control
-all Restores or indexes all the objects in the back up file
specified. This option is required if you do not use the
pathname argument to indicate a particular object to be
indexed or restored.
-as pathname1 Restores the object specified and assign a different disk
pathname pathname1. This option is valid only when used
with the pathname argument on the rbak command line.
-cr (default) Specifies create mode. rbak does not restore objects if
their names already exist on disk. It prints an error
message if a name exists on both disk and backup media,
and continues.
-r Specifies replace mode. rbak deletes the existing disk
object, and replaces it with the object read from backup
media.
-force Forces object deletion if you have owner rights, even if
you don't have delete rights.
-du Deletes when unlocked. If the object to be deleted is
locked when rbak is invoked, the delete operation is
performed when the object is unlocked.
-ms Specifies merge-source mode. Similar to replace mode. If
an object already exists on disk, rbak deletes the disk
version and restores the backup media version (the
source). However, if the object is a directory, rbak
merges the back up media directory's contents with the
disk directory.
-pr pathname...
Preserves specified objects on the disk. Multiple
pathnames and wildcarding are permitted. If the objects
exist on disk, they are not overwritten by backup media
versions. This option must be used with the -ms option.
-md Specifies merge-destination mode. Similar to create mode.
If an object already exists on disk (the destination) rbak
does not restore the backup media version, and retains the
disk version. However, if the object is a directory rbak
merges the backup media directory's contents with the disk
directory.
Label Control
-sla (default) Displays the backup media file label on standard output.
-nsla Does not display the backup media file label.
Listing Control
You may include the -l option, or any combination of -ld, -lf, and -ll.
-l Writes all the file, directory, and link names to standard
output.
-ld Writes all directory names to standard output.
-lf Writes all filenames to standard output.
-ll Writes all linknames to standard output.
Backup Device Control
-anys Forces rbak to accept any section of the backup file. When
a backup file spans multiple backup media volumes, rbak
normally begins with the backup media volume containing
the backup file's first section, and proceeds to the
backup media volume containing the second section, and so
on. If you know which backup media volume contains the
object you want to restore or index, use this option.
This lets rbak start at any section of the backup file.
-reo Forces previous volume to be reopened, and suppress
reading of backup media volume label. Use only when
backup media has not been repositioned since the last wbak
or rbak.
-dev d[unit] Specifies 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). If this option is omitted, rbak assumes
device m0.
Note: 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 is critical and unrecoverable.
-from filename Reads the backup input from a file written by wbak using
the -to option. filename specifies the pathname of the
file.
-stdin Specifies the backup input media to be standard input.
Used along with I/O redirection, this option is useful for
reading files from foreign file systems.
-reten Retensions the cartridge tape (unwind to the end, then
rewind). This can be helpful if you encounter cartridge
tape reading errors. Retensioning requires about 1.5
minutes to complete.
-nreten (default)
Do not retension the cartridge tape.
-unload Unload the tape at the end of the backup session. This
option is valid for reel-to-reel magnetic tapes only.
-rewind Rewind the tape after reading or indexing. If this option
is omitted, the tape is left positioned to the next tape
file.
ACL Control
-dacl (default)
Assigns the destination directory's default ACL to the
object being restored.
-sacl Retains the restored object's original ACL.
-pdt Preserves the object's original date-time modified and
date-time used.
EXAMPLES
$ rbak -f 1 fred/soup
Read fred/soup in backup file 1 and restore it to disk. fred/soup may be
a directory, file, or link.
$ rbak -f 1 fred/soup -as //node5/noodle
Restore fred/soup and place it in noodle on node5.
$ rbak -dev ct -rewind
Rewind the cartridge tape prior to removing it from the tape unit.
$ rbak src -from /fred/bck_out.file
Restore the directory src to disk. Read the backup input from the file
/fred/bck_out.file, that should be written by wbak using the -stdout or
-from option.
$ catf /fred/bck_out.file | rbak src -stdin
Restore the directory src to disk. Read the backup input from standard
input. Note that the file /fred/bck_out.file should have been written by
wbak using the -stdout or -from option.
SEE ALSO
More information is available. Type
help wbak For information on creating a magnetic media backup file
help rwmt For information on reading/writing foreign magtapes
help media For information on removable media