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Receiving PI point updates with PIDataPipe and WindowsAuthentication

Question asked by dpilc on Aug 10, 2017
Latest reply on Aug 11, 2017 by Marcos Vainer Loeff

I'm experiencing somewhat mysterious behavior of the PIDataPipe subscription mechanism in PI AF SDK.

I've a piece of code, similar to the one given here https://techsupport.osisoft.com/Documentation/PI-AF-SDK/Html/T_OSIsoft_AF_PI_PIDataPipe.htm, that subscribes for PIPoint updates. Also, I'm able to create two independent PIDataPipe instances for two separate subscriptions (for different sets of PIPoints). It kinda works if my app authenticates itself using a PI trust.

The problem arises when I use Windows Authentication and add lines of the form

 

System.Net.NetworkCredential cred = new System.Net.NetworkCredential("myusername", "mypassword", "mydomain");

myPIServer.Connect(cred, PIAuthenticationMode.WindowsAuthentication);

 

to my code.

I run `Connect` only once at the beginning but I can see in the PI message log that everytime when a new subscription gets created (via `PIDataPipe.Subscribe`) a separate connection is made to the PI server (this was not the case with no explicit `Connect`). What is more troublesome is that new connections (i.e. new subscriptions) break previous subscriptions - I receive no errors, events just stop arriving for old subscriptions (I only get notifications for the very last subscription).

 

Has someone else experienced the same issue?

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