Hello Experts,

I have an OPC server (Kepware KEPServerEX) hosted in the cloud. Inside Kepware, I have two OPC UA connections configured:

• WinCC01 → points to my physical WinCC Server S1, with redundancy enabled to S2.
• WinCC02 → points directly to my physical WinCC Server S2, with no redundancy configured.

Problem

The connection WinCC02 → S2 sometimes completely loses the OPC UA connection.

On the WinCC S2 side, the Runtime keeps running normally (no crash).
However, Kepware cannot reconnect to S2 unless I stop and restart Runtime on the WinCC server.

I have already checked:

• The TCP port for OPC UA is open.
• Windows services for WinCC OPC UA are running.
• Compared running services between S1 and S2 → no differences found.

What could cause WinCC OPC UA server (S2) to “hang” a session and not allow Kepware to reconnect?

Please, does anyone have experience with this behavior? Any advice?

Hello Murof

Thanks for your support.

In the folder diagnose there are not relevant information about the OPC UA connection.

and I have installed this versions.