Disaster Recovery configuration - System Failure

[ilyas_ahmed]

Hi Experts,

My question is regarding Disaster Recovery Configuration failure case when the failed MCS returns back to normal.

In that case , How historic data of MCS is synchronized with DRS data base, after MCS is normal again after a fault?
How Oracle cluster will be synchronized? Is it automatic or manually triggered?

I have seen one FAQ on that which is as follows. As per this FAQ the matching of MCS and DRS data bases should be initiated manually. My question is that why it is not automatic and what if operator forgets to initiate the manual synchronization. What could be the consequences?

7. HOW DOES THE MATCHING OF HISTORIC DATA WORK AFTER A CONNECTION BREAKDOWN?
The matching of historic data (RDB) after the fault event is manually initiated (when the necessary network bandwidth is available again). For this, the user has access to a special control panel, on which alterations to be synchronised are displayed. The matching of historic data (e.g. after a connection breakdown between MCS and DRS or a system failure at DRS) is not automatically carried out but must be initiated by the operator on the control panel.
Can you please explain me a bit more on that.

Thanks a lot

Regards,

Ilyas.

[tkulmuk]

Hi Ilyas,

The description of how to start up the data sync after failure is provided in the online help: Add-ons->Disaster Recovery System->Configuration of the Disaster Recovery System->Synchronization of historical Values in the Database.

It is not triggered automatically by default, because it depends on multiple factors (i.e. available network bandwidth and data size to be synchronized).

Nothing critical could happen if operator forgets to initiate synchronization. One set of historical data will be available in MCS Oracle database and another data will be available in DRS Oracle database until the databases are not synchronized. Online data is synchronized over DIST.

Br,
Tagir

[ilyas_ahmed]

Hi Tagir,

Thanks a lot for your reply. I was looking for this information and yes WinCC OA online help is quite comprehensive.

Best Regards,

Ilyas.