Data Replication - Siemens SIMATIC BATCH Operating Manual

3.5.5.4

Data replication

Synchronizing databases
Each redundant BATCH server of a server pair (master, standby) has its own local database.
To continually synchronize the two local databases, an independent second network adapter
is used for each of the two server PCs. The following tasks are performed via this connection:
● Lifebeat monitoring of the redundant partners
● Data replication
● Data consistency between the redundant partners
This ensures that both BATCH server always use the same database.
Redundancy switchover, start sequence of the BATCH servers, database synchronization with WinCC
message
● An interruption of the replication connection (extra network adapter in both redundant
SIMATIC BATCH server PCs with network cable) affects the communication between the
AS and the BATCH server. The communication is blocked for approximately 20 s. This
means that the process (batch) continues running but its visualization in the BATCH Control
Center or in the BATCH OS controls is updated after a delay of up to 20 s.
● When starting a redundant BATCH server or during a redundancy switchover, the
databases of the standby server are synchronized with the databases of the master server.
Do not abort the copy procedure needed for this, e.g. by powering down/switching off one
of the BATCH servers. If you do, you will have to reset the BATCH database of the standby
server.
● A "Restart dialog" appears on the previous master once a switchover to a redundant pair
of servers caused by an error has occurred. Please follow the restart request to correctly
restart the PC. All active programs are closed when you acknowledge the restart request.
SIMATIC BATCH V8.2
Operating Manual, 02/2016, A5E35958174-AA
Product introduction and installation
3.5 Possible configurations
57