2 modbus requesters on the same client IP targeting the same modbus server IP

Hi, I have the following config, and I would like to have your advice :

  • On system with IP1 : 2 modbus clients (2 different SCADA systems)
  • On system with IP2 : 1 modbus server (the machine PLC)
  • The modbus link in Ignition tend to disconnect every one and then

I know it's not the best option to have 2 SCADA coexist on the same host, and I'm requesting a separate system for this purpose. But in the meantime, to run my testings, this system (IP1) is the only one from which I can access all PLC and industrial LAN.

Here's my question :
When both clients send modbus requests at the same time, is there a way to avoid conflicts, and make sure the response will get to the proper requester ?

If this is Modbus TCP there should be no conflicts unless the server you’re communicating with has a broken implementation.

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Check if the machine PLC has a setting for how many modbus TCP clients are allowed.

If it is not modbus TCP, then you will need a modbus gateway device to manage the traffic.

Got it, it's Modbus TCP, so I'll check the implementation/limitations on the modbus server side.
thanks fo your guidance @Kevin.Herron @pturmel