advanced modbus falure and geo scada server changed state!!

[BGedco2022]

Hi,

Our client has geo scada on a main-standby architecture.

after upgrading geo scada into the latest version, the advanced modbus driver fails unexpectedly which lead to lose connection  from all modbus channels.

in events log, There's no explanation for that.

we also noticed that, prior modbus driver fails, the server state changed from main to standby then get back to main in less than a minute!!

Is there any suggestions ?

and what are the events or situation the lead to change the server state??

Appreciate any help ^_^

[sbeadle]

This looks like a complex issue. Please may I suggest you contact the support team and request assistance?

They will want to see DBServer log files and Modbus driver log files.

[BevanWeiss]

As Steve has mentioned, this does sound a little more complex than a forum post will resolve, so contacting your local tech support seems the best path to proceed down.

From what you've mentioned, my immediate thought is that this is a Heartbeat failure (or potentially Dead Lock detection, if you have this enabled).

This can result in the Main/Standby roles toggling, and for drivers like Modbus where only the Main server is allowed to perform operations it would also result in quite a few communications failures.

So suggestions would be:

1. For testing, disable the deadlock detection in the Server Configuration for the server.
2. Check the Server Snapshots to see what your DB lock % is, and what the longest lock times are.  If the longest lock time is greater than a few seconds you will start to see issues (ideally having locks in sub-seconds is best).

You may be seeing increased logic execution or similar.  I'm unsure of any major changes in the Modbus driver in the recent update, but you may want to review the change logs to see if there is anything that might be causing increased server load.