To add to the investigation.
We have two units that stopped responding today, one would not work through DmD and required hard disconnect.
Both on the latest FW.
PLC1:
VPN connection primary office, connected to RS485 flowmeter.
This has two SCADA machines that collect data (across the VPN), PLC is the Server (Slave) via Modbus TCP.
Additionally onsite there is an AVG (EZTouch) HMI on the Ethernet system, all wired.
PLC had 8 connections in config, all 8 were occupied and would not clear. We forced the two SCADA servers to disconnect (Out of Service).
The connections would not timeout on PLC status. After 5 minutes we performed a software REBOOT instructions.
Connections reestablished, shows 3 active now.
PLC2:
VPN Connection to primary office, connected via Ethernet to MDS SD4 (1) radio and RS232 to additional SD4 (2).
Single SCADA server on VPN connected to PLC Modbus TCP Server. Five remote sites polled by the PLC, Modbus TCP Client, via SD4 (1).
Slave connection, Modbus RTU, on SD4 (2); built in port.
Site stopped responding to Client requests from SCADA and also stopped polling slaves at the same time via TCP/Ethernet.
Could not connect to DmD, no response.
PLC continued to respond via serial connection as Modbus RTU slave.
Required a physical power disconnect.
So virtually all of our BRX units with Ethernet connections are beginning to exhibit these problems.
All are on the latest firmware.
Unfortunately, it is not happening on only MWX/MRX configured devices now, it is even on slave only units. Albeit different types of failure (max connections vs. unresponsive device)
