DCOTTLER%rca.com@RELAY.CS.NET (Dan Cottler) (09/04/86)
The following article was posted on the Digital Software Information
Network back in April. It contains patches that will fix the density
changing problems...
BACKUP-E-DENSITY Error On 2nd Tape Volume: VMS V4.3
DATE: 04-Apr-1986 13:27:00
OVERVIEW:
This article contains a patch to fix a problem with the BACKUP utility.
DIGITAL recommends that you do not apply this patch unless you are
experiencing the precise symptoms detailed in the statement of the problem
below. Also, if you anticipate that you might experience this problem because
you make use of the BACKUP utility you should apply this patch. If you are
encountering other symptoms associated with the use of BACKUP please contact
your Customer Support Center to obtain more system- or situation-specific
information.
The total length of this article is approximately 155 lines.
CAUTION *******************************************************************
This patch must be applied ONLY on version V4.3 of VMS. It must be entered
EXACTLY as shown. Please be careful to enter all letters (in UPPERCASE)
and numbers as indicated, observing the spacing as shown.
ALL COMMENTS MUST BE INCLUDED. ALL SPACING IS DONE WITH A SINGLE SPACE
CHARACTER; TABS AND DUPLICATE SPACES DO NOT EXIST IN THE PATCH FILE.
The patch file will checksum itself, and the patch file will not execute
unless the checksum is correct. Failure to make use of the checksum (i.e.,
circumventing the checksum steps by simply patching the image given the
information in the patch file) may corrupt the image you are patching, and
leave you with an unusable operating system and/or utility.
**************************************************************************
PROBLEM STATEMENT:
Backup operations to tape that require more than one tape will receive
the following error message on a volume switch:
%BACKUP-E-DENSITY, "saveset" does not support specified density - default
used
This error will occur ONLY on the 2nd reel and not on subsequent volume
changes. A side effect is that BACKUP will write to subsequent tapes at
the density the tape was previously written. This means that if one is
doing a backup operation at 6250, and the backup command does not include
/DENSITY, BACKUP will start writing at 1600 BPI if the new tape mounted
on the drive had been previously written at 1600 BPI.
WORKAROUND:
To prevent both the BACKUP-E-DENSITY message and a density switch, use the
/DENSITY qualifier on the backup command. In situations where it is
undesireable to modify existing procedures, a global symbol can be set up as
follows:
BACKUP = "BACKUP/DENSITY=x"
This global symbol can be set up in SYS$MANAGER:SYLOGIN.COM if needed.
This workaround does not apply if your tape drive either supports 6250 BPI
or caching. Currently, the only tape drive that supports caching is the
TU81E. In such cases, we recommend that the following patch be applied.
Additionally, we recommend the application of the patch if the workaround
given does not suit your needs.
PROCEDURE FOR APPLYING PATCH:
1. Log in to the system as username SYSTEM (the account reserved for
software updates).
2. Set your default directory to SYS$UPDATE with the command:
$ SET DEFAULT SYS$UPDATE
3. The following patch will patch your backup image that is used for online
backups. Create a file called BACKUP.PAT, which contains the following 21
lines of text:
-------------------------------------------------------------------------
$ CHECKSUM BACKUP.PAT
$ X='CHECKSUM$CHECKSUM'
$ IF X.NE.%X37204B55 THEN GOTO IC ! 37204B55
$ ON WARNING THEN EXIT
$ SET DEFAULT SYS$UPDATE
$ COPY SYS$SYSTEM:BACKUP.EXE BACKUP.EXE
$ PATCH/JOUR=BACKUP/OUTPUT=BACKUP BACKUP
SET ECO 3
VERIFY/BYTE 103D7=31
DELETE/INSTRUCTION 103DE='MOVL R0,R8'
EXAMINE/INSTRUCTION 103D7
DEFINE DEST_3=\
INSERT/INSTRUCTION DEST_3='CALLS #01,L^0000F5D6'
'MOVL R0,R8'
EXIT
UPDATE
$ COPY BACKUP.EXE SYS$SYSTEM:BACKUP.EXE
$ DELETE BACKUP.EXE.*
$ EXIT
$ IC:WRITE SYS$OUTPUT "INCORRECT CHECKSUM; VERIFY CONTENTS OF FILE"
$ EXIT
-------------------------------------------------------------------------
4. Execute the patch command file with the command:
$ @BACKUP.PAT
5. You may delete the BACKUP.PAT patch file once you have successfully
applied the patch, or you may leave it on your system for potential future
diagnostic needs.
6. The following patch will patch your backup image that is used for stand
alone backups. Create a file called STABACKUP.PAT, which contains the fol-
lowing 21 lines of text:
-------------------------------------------------------------------------
$ CHECKSUM STABACKUP.PAT
$ X='CHECKSUM$CHECKSUM'
$ IF X.NE.%X513D4F57 THEN GOTO IC ! 513D4F57
$ ON WARNING THEN EXIT
$ SET DEFAULT SYS$UPDATE
$ COPY SYS$SYSTEM:STABACKUP.EXE STABACKUP.EXE
$ PATCH/JOUR=STABACKUP/OUTPUT=STABACKUP STABACKUP
SET ECO 4
VERIFY/BYTE 12DDB=17
DELETE/INSTRUCTION 12DE2='MOVL R0,R8'
EXAMINE/LONG 12DDB+2
DEFINE DEST_4=.+\+4
INSERT/INSTRUCTION DEST_4='CALLS #01,L^00011FDA'
'MOVL R0,R8'
EXIT
UPDATE
$ COPY STABACKUP.EXE SYS$SYSTEM:STABACKUP.EXE
$ DELETE STABACKUP.EXE.*
$ EXIT
$ IC:WRITE SYS$OUTPUT "INCORRECT CHECKSUM; VERIFY CONTENTS OF FILE"
$ EXIT
-------------------------------------------------------------------------
7. Execute the patch command file with the command:
$ @STABACKUP.PAT
8. You will need to reinvoke STABACKIT.COM to recreate your stand-alone
backup kit.
9. You may delete the STABACKUP.PAT patch file once you have successfully
applied the patch, or you may leave it on your system for potential future
diagnostic needs.
[end of article]