Redundent WinCC OA Servers

[uxout]

The server have multiple connections, one of them is for client network where the UI's are running from.
If the switch from client network fails, every other connection are still ok (like PLC's)

[NikolayLevchenko]

Well, BOTH servers will have all other connections working OK, right?
In your diagram the only difference between server A and server B is that server A does not have a client connected and server B does. Hense, server A will have a higher error state (if you configure error weight on the UI connection).

[uxout]

Yes true, this case is OK.
What I wanted to point out is when no client is connected at the beggining and the first client try to connect to the servers.

[NikolayLevchenko]

Well, when NO client is connected to BOTH servers, they will BOTH have the same error state. Whichever server the client will connect fist, will become ACTIVE since it'll have a lower error state earlier than the other server. I think I also configured a small (few seconds) delay for redundancy switch-overs to avoid ACTIVE/PASSIVE switching too many times when the system is starting and establishing comms to PLC's and UI's

[uxout]

WCCOAui (0), 2018.03.06 16:42:36.801, SYS, INFO, 1, Manager Start, PROJ, testRedu, V 3.15 - 3.15 platform Windows AMD64 linked at Feb 6 2018 17:51:15
WCCOAui (0), 2018.03.06 16:42:36.852, SYS, INFO, 3, Trying to connect to (SYS: 0 Data -num 0 CONN: 1) @ S-WINCCOA-P1:4897$S-WINCCOA-P2:4897
WCCOAui (0), 2018.03.06 16:42:50.074, SYS, INFO, 4, Connected to (SYS: 0 Data -num 0 CONN: 2) @ S-WINCCOA-P2 (fe80::6c14:9a58594e%4)
WCCOAui (0), 2018.03.06 16:42:54.638, REDU, INFO, 0, , Closing connection to passive data during initialization. This may terminate the manager., (SYS: 0 Data -num 0 CONN: 2)
WCCOAui (0), 2018.03.06 16:42:54.648, SYS, INFO, 181, Closing connection to (SYS: 1 Data -num 0 CONN: 2)
WCCOAui (0), 2018.03.06 16:42:54.655, IMPL, FATAL, 5, Connection not possible, WCCILdata

This is the error I got from my client when I try to connect to the servers (passive one at first).
I didn't set "connectToRedundantHosts" yet, should this resolve my issue?

[NikolayLevchenko]

Yeah, give that a try

[uxout]

Just tried, it doesn't change anything

[leoknipp]

A UI in a redundant system is automatically using "connectToRedundantHosts".
The option is not used if the UI is started with -data -event with only one hostname, e.g. to start a UI in split mode to connect one server.

Best Regards
Leopold Knipp
Senior Support Specialist

[uxout]

Good to know, thanks