We're using DeltaV inter-zone servers to transfer data from a V14.3.1 system to a V12.3.1 (soon to be upgraded) via a VPN tunnel on our corporate WAN. The WAN link between the two sites is provided by a telco, as the sites are located more than 600km apart.
Multiple times each day the inter-zone modules report "General I/O Failure" which is a nuisance but manageable. Unfortunately there doesn't appear to be an option to "tune" the inter-zone communications for the WAN link, so we just need to ignore these alarms if they clear within a few seconds.
Every few weeks, though, we need to restart the inter-zone servers on the V14.3.1 system (data source) to reinstate the inter-zone communications. So far we've not been able to find any obvious cause - the link just stops working.
We already have an OPC Mirror server on the V12.3.1 system, but would need an additional license to allow it to be used to connect these two systems. I'm wondering whether that might prove a more reliable solution.
My questions for the gurus:
1. Has anyone else encountered, and more importantly managed to resolve, similar issues with inter-zone server failures?
2. Would an OPC mirror solution potentially be more robust for data transfer between two DeltaV systems over a WAN connection?
Thanks