NOUNLOAD
The NOUNLOAD option directs BACKUP to rewind the final tape and leave it online when the
BACKUP process is completed.
NOUNLOAD
CAUTION:
Using BACKUP with the NOUNLOAD option leaves the tape online and write-enabled.
Subsequent BACKUP commands (either from you or another user) could write over the data that
was just backed up. If you are backing up critical data, do not use the NOUNLOAD option unless
there is no possibility that the tape can be inadvertently overwritten. The use of the NOREWIND
option will prevent another process from using the drive until the drive is manually reset. The use
of labeled tapes with a TAPECATALOG DEFINE can also prevent other users from overwriting the
tape.
NOUNLOAD is mutually exclusive with NOREWIND. If neither is specified the default is to unload
the tape.
OPEN
The OPEN option directs BACKUP to back up files even if they are currently open with write or
read/write access unless the files are also open with exclusive access.
If you do not include the OPEN option, the BACKUP process skips the files and ERROR-3012 is
issued on files that are currently open with write or read/write access. To avoid this error, use
WHERE NOT OPEN as the WHERE
expression
qualifier. Using this qualifier results in the
BACKUP process skipping the files that are currently open and an error is not received. For more
information about the WHERE NOT OPEN qualifier, refer to
File Attributes (page 45)
.
OPEN
CAUTION:
If you restore a file that was modified or open for write access while being backed
up, file-system error 59 (file is bad) can occur, and data can be lost. Whenever possible, close all
files before running BACKUP. If audited files are backed up in the WRITE OPEN state, they could
be corrupt. Restoring such files and using them in audited mode can cause TMF to leave the whole
volume in an inconsistent state. If audited files are restored, they should be used in nonaudited
mode. Use TMF to dump audited files to tape.
Guidelines
•
BACKUP normally tries to open files with protected read access, meaning that other processes
can read the files but cannot write to them. If the OPEN option is in use and BACKUP fails to
open a file with protected access, BACKUP then attempts to open the file with shared read
access.
•
For additional information about backing up files that are open and audited, see
AUDITED
(page 48)
.
•
Before backing up files with the OPEN option, issue an SCF CONTROL DISK, REFRESH
command to update file labels on disk. Then be certain the files being backed up are not
modified while BACKUP is running.
BACKUP Options
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