User Manual

Siemens Building Technologies VISONIK DCS Functions and System Messages VVS18 CM2U8567E / 04.1999
Landis & Staefa Division Function BCKP 2-5
2.2 BCKP Shadow Backup
2.2.1 Initial Access and Handling
CTRL/P BCKP
T8 15?42:37 Function=PNT : BCKP
To=DU1: : ?
To=SYS:,SY0:,SY1:,DU0:,DU1:,DU2:,DU3:,DU4:,DU5:,DU6:,DU7:DM0:,DM1:,DM2:,MM0:
Function BCKP allows on-line copying of a 'Shadow' version to a backup device which
may be a tape unit or a VISONIK structured disk.
When a backup device is specified various plausibility tests are carried out and where
necessary an error message given:
"These disk-selection is not allowed"
The help information on permissible devices is formulated in very general terms.
ONLY
the following devices are permitted for backups:
Logical names for various devices
DU2: Device Unit '2'
.... ....
DU7: Device Unit '7'
Logical names for tape drives
MM0: Tape '0'
MM1: Tape '1' (if present)
2.2.2 Procedure
Define the Shadow at the VISONIK DCS (SYS,DISK).
Prior to the actual backup the function
automatically
initiates the creation of a
Shadow.
This is identical to the parameter change
$SY,SHAD=OnOf.
The actual copy operation is then started.
1. The Shadow version is restructured if it is older than 1 hour. This restructuring is
signalled by "Please wait!".
2a Backup on tape:
On every backup the tape is re-initialised for the actual version's size. The
Shadow version is then copied to tape after which a comparison is made
between the two Shadow versions.
2b Backup on Diskettes:
dialogue. The number of diskettes required is then prompted. Each diskette is
initialised before copying starts.
3. After backup is finished a comparison between the original Shadow and backup
versions is made. Any discrepancies are listed showing the exact block number
and checksum.
Since the above described sequence takes place in a dialogue process it must not be
interrupted through any actions from the associated terminal (e.g. with Ctrl/P!!).
Otherwise the backup procedure is aborted and must be restarted.
Function call-up
General
Permitted backup
devices
Prerequisite:
Actions of BCKP:
Important