Slow respons with all controllers due to lost connection with one of them


On my plants Ignition server we have connected several S7 controllers, most of them connected with IP address and only one connected with OPC-UA server (UPC-UA server in the S7-1200 PLC).

The other day we lost connection to the PLC connected with OPC-UA. The result of this was that all other S7 controllers gained a extreme respons time to any tag change, especially when writing to single bits.
When disabling the PLC with the lost connection, the other S7 controllers started working normal.

Below you can see the settings for the PLC that now is disabled due to lost connection (wiring fault).

All settings are as default.

Does anybody know why a lost connection to one PLC affects the rest of the connected controllers?

Best regards,

What version of Ignition are you using?

Version: 8.0.15

Okay, I think this was fixed in 8.1.3. This is the release note:

Use separate batches for writes to different OPC servers to prevent a slow-responding server from blocking an unrelated write to a fast-responding server.

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