CS redundancy with AE
I have a redundant Connectivity Servers and I have a question regarding connecting to the controllers using OPC configuration panel, should I tick OPC AE on both server when connecting to the controller or not? Because when ticking that on CS2 it gives me a message that I exceeded the limit of number of subscriptions. In addition to that, in the service structure, I can see both services (AC 800M service provider AE on CS1 and CS2) as synchronising and not service and standby is that normal?
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in the AC800M CPU settings there is a Parameter for maximum allowed AE Subscribers. It looks like you already reached the max. number of subscribers for any reason. So please check that setting if it fits to your needs, modify it or remove unnecessary AE Subscribers
For the AC 800M OPC server to announce an OK state it must have a valid connection with at least one controller. The DA and AE tabs are supervised individually (each have a separate status that must be OK for the 800xA OPC DA Connector and Event Collector services to be satisfied).
The typical problem is a too low setting of AE Max No Of Subscribers, which defaults to 1, which only permit a singular OPC server to connect. Increase to two or more (e.g. if PP800 shall connect over AE) and download. In severe cases AE queue slots become stuck and you must perform a controller reset to free it (or download +1 on the aforementioned setting to create a free slot).