Third party OPC data only available on certain operator stations

We have configured third party OPC communication between two 800xa systems in different domains.

The OPC DA service provider is in service, Dcom settings are proper. I am able to get data in both matrikon and advdsopcclient .

But when I subscribe in control structure in any server the status shows Bad(communication fail).

Only in two out of 10operator stations I am able to subscribe and get good quality for the third party OPC data.

Has anyone faced this kind of problem?

Please suggest what can be done to rectify this?

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milind1076 Rank: 617

Asked 3 years ago

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Bad (Comm fail) is very likely coming from the true source OPC server due to some configuration error. (i.e. not an error from the link connecting the two systems)

How did you configure the link? Generic OPC upload?

Check if OPC item ID in Control Connection aspect (created at upload of) is correct.

The recommended intra-system communication method is Multisystem Integration, not OPC.

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by milind1076 Rank: 617 on 4/18/2017 8:10:53 PM | Like (0) | Report

We have browsed for the tag via matrikon and then used the same path in control connection. If the source opc had bad data it would show bad in matrikon as well.
Also we are able to get data in two xa nodes.
Aspect server secondary is used as a connectivity server in this setup

by Stefan Stromqvist AKS expert

Rank: 1 on 4/18/2017 11:30:42 PM | Like (1) | Report

If some 800xA nodes get data, all should. Only thing I can think of here is
a) Affinity blocking access for some clients
b) Bad data in hosts file(s) (wrong IP somewhere)

But in general, when workplace, etc can not reach OPC DA Connector, the OPC Quality "Bad (Not Connected)" is displayed. Try by "blocking" a client using affinity.

*Desktop* clients such as Matrikon and AdvDsOPCClient.exe can not straightforward be compared with the OPC DA Connector service that runs as a *service*. DCOM settings must allow connector to launch OPC server, but DCOM settings must also allow OPC server to perform asynchronous callbacks to connector. Bi-directional DCOM settings are sometimes required (e.g. if server and connector runs under different user accounts).

by milind1076 Rank: 617 on 4/20/2017 7:00:03 AM | Like (0) | Report

Thanks a lot for your support. Indeed it was affinity that was blocking the data. Once I added As-r server in the cs-affinity list, I was able to get the data in all systems.
Once again thanks a lot.

by Stefan Stromqvist AKS expert

Rank: 1 on 4/20/2017 7:14:49 AM | Like (0) | Report

Good work!

I also see that "(Bad) Comm failure" can be returned when affinity is blocking. I previously thought "(Bad) Not Connected" was the only one.

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