800xA SV5.1 for MOD300 OPC SERVER FAILURE

I discovered a problem on a 800Xa sv 5.1 dcs with 800xA for MOD300 connectivity.

There we have a system with n. 2 AS, n.4 CS , n.1 IM and n.1 OPC for MOD standard.

and n.6 800xA clients. We have Affinity settings to have odd server for odd clients (e.g. AS1,CS1 works for client1, client3 and AS2, CS2 for client2, client4 etc....) adn even server for even clients priority load balancing.

Last night we had a failure of the OPCDA service provider of Connectivity Server CS1

and odd clients (1,3,5)stopped displaying loop data on the respective workplaces, whilst the even clients (2,4,6) were working perfectly.

The odd clients did not switched to connectivity server CS2..

The only way to reset the situation was to disable and re-enable the "failed" OPCDA service provider. At that time all the clients even and odd ones started immediately

to operates again. I would like to know if anyone experienced similar problem related

to the redundancy of the OPCDA service provider for MOD300 Connectivity server.

The problem appears randomly and obnly in OPCDA server pairs and not for OPCAE service groups . Thanks a lot for help.

Regards,

Paul