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  9. Prevent the session from disconnecting when write activity is intermittent?

Prevent the session from disconnecting when write activity is intermittent?

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19 Aug 2024 14:44 #13027 by support
Replied by support on topic Prevent the session from disconnecting when write activity is intermittent?
Hello.

There is no limit (except Int32.MaxValue) to the number of locks. Two or more locks are not a problem. What matters is whether the total lock count on the endpoint is zero, or non-zero. When it is non-zero, it is locked. When it goes back to zero, it unlocks.

If the connection to the server is lost, the existence of the lock assures that QuickOPC will keep retrying to reconnect. The lock is not affected and the handle stays valid. Do not reacquire the lock.

Regards

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19 Aug 2024 13:36 #13026 by JosephJ
Replied by JosephJ on topic Prevent the session from disconnecting when write activity is intermittent?
Thank you! Option 2 seems to be what I am looking for.

Are there any restrictions to how many locks that can be created? Is there an upper-bound limit?

If two locks are created to the same endpoint, will this cause an issue?

Lastly what happens if the server loses connection? Does the lock handle become invalid? Will the lock need to be required again


Thank you again for all the help!

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16 Aug 2024 08:47 #13022 by support
Replied by support on topic Prevent the session from disconnecting when write activity is intermittent?
Hello.

There are following options:

1) Increase EasyUAClient.IsolatedParameters.SessionParameters.HoldPeriod.
2) Recommended way: Use connection locking service:
- opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Late...tion%20Control%20Services.html
- opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Late...20unlock%20a%20connection.html
3) Or a poor man's solution: Any subscription you make to the server keeps the session open until all subscriptions are explicitly unsubscribed from your code.

I hope this help
Best regards

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15 Aug 2024 16:50 #13019 by JosephJ
Prevent the session from disconnecting when write activity is intermittent? was created by JosephJ
Is there a way to keep the client session active with the server and not time out due to inactivity?

I tried using the below settings, but this did not yield the intended results. I am looking for a way to write a tag value to the certain and intermittent times. Being able to write a value, and then go some period of time without needing to reconnect to the server due to inactivity?

Is there a setting I can apply that will achieve this or must I poll/write a value at a constant interval to maintain session connection?

 

 

      _opcClient.Isolated = true;

      _opcClient.IsolatedParameters = new EasyUAAdaptableParameters()

      {

        SessionParameters =

        {

         SessionConnectTimeout = UAClientSessionParameters.DefaultSessionConnectTimeout,

         SessionTimeout = UAClientSessionParameters.DefaultSessionTimeout,

         KeepAliveInterval = UAClientSessionParameters.DefaultKeepAliveInterval

        }

      };

 

 

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  9. Prevent the session from disconnecting when write activity is intermittent?
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