Westinghouse SE 6000 - Manual (Page 139)

S
ECTION
6: S
YSTEM
A
DMINISTRATION
6-15
D
ATABASE
B
ACKUP
. A database backup copies all information in the database (exceptions user and map
information). If you make a number of changes to keyholder, hardware, and / or access
information in a single day, then the database backup should be performed each day. For these
purposes, use two alternating tapes (one for odd days, one for even) to guarantee that no
information will be lost in the event of a hardware malfunction.
F
ULL
V
OLUME
B
ACKUP
. A full volume backup copies all system data including programs, system
configuration information, and user / map information. The backup tape created is used to restore
the system in the event of a hardware malfunction. A full volume backup should be performed
immediately following system installation, and then on a monthly basis or whenever there has been
a major system update or reconfiguration.
D
OWNLOAD
C
LEAN
U
P AND
R
ETRY
[downcln]
Download records are data transferred from the database to computer memory or to intelligent
remote devices. Each time information is entered and stored in the database, one or more
download records are created and written to the download file. If the download transfers are
unsuccessful, the number of records created can increase the download file size to a point where
system performance is affected, and these records should be first retried then deleted. In general,
perform a download cleanup when the PUBLIC.download table reaches 80% of the expected
number of rows, or if it has been necessary to make a significant number of database changes.
Monitor this table using Display Database Statistics [dbstats].
If you use a large number of intelligent devices, then this table should be checked frequently. A
typical time period for cleaning the download table is once per month. Download records are not
automatically deleted upon successful transfer.
A
CCESS
C
ONTROL
T
RANSACTION
A
RCHIVING
[accsarch]
Archiving transfers information from the system hard disk to tape, freeing up space on the hard
disk for new data. Archiving should be performed regularly to ensure disk integrity. Perform an
archive when the PUBLIC.archist table reaches 80% of the expected number of rows. Monitor
this table using Display Database Statistics [dbstats]. Archiving is usually performed monthly or
every two months. Note that unless necessary for reporting purposes, WSE recommends that you
archive system information when your transaction volume reaches 100,000 records.