We are currently using Autosol with OPC-UA. When switching devices in Autosol from Totalflow protocol to ROC protocol we are just getting bad quality data in Ignition. I have worked heavily with Autosol support trying to resolve. It appears with our testing using UA expert, we just need the client (Ignition) to release the current subscriptions and re-subscribe to the items. How do you manually trigger a release OPC items and re-subscribe on a UDT? We just recently switched from OPC-DA and I am fairly new working with OPC-UA.
The biggest hammer you could swing would be edit/save the OPC UA connection to that server.
Less disruptive, you might be able to right-click -> restart on the tags in question, but it depends whether re-creating the Monitored Items is enough or if the actual Subscription has to be re-created as well.
This is all symptomatic of a broken OPC UA server though. You shouldn't have to do this.
As of now stopping / restarting the Autosol OPCUA service is the fix, but extremely disruptive. Very similar to breaking the connection like you mentioned. I will give the restart tag a try.
Autosol support mentioned that is just the way OPC-UA worked and no way around it. I initially thought it was the OPC server side also, that is why I started with Autosol support.
How should the OPC server handle this type of change normally? Maybe some info you could provide I could take back to Autosol support to push for that resolution on the Autosol end.
I don't really have all the details here, but this sounds like it's something a little outside the OPC UA spec and more of an implementation detail of their server.
From the OPC UA client perspective, if the connection to the server remains alive, the session remains alive, then the subscriptions are still valid, and the monitored items are still valid, and whatever is happening on the backend when you "switch devices" shouldn't matter.
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I'm having the same issue - I have to re-start the OPC-UA server to get it to resubscribe.