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ModbusTCP capture not working on certain Laptops

Good morning, I am finding a strange problem and my company IT guy cannot figure out too. For a test I have three laptops running wireshark, installed absolutely the same way (default setting, full install, same version): -LaptopA=company laptop, windows 11 -LaptopB=company laptop, windows 10 -LaptopC=personal laptop, windows 10

When I capture packets from a mirror port of a switch or of a PLC, with LaptopsA&B (the company laptops) it captures all but fails capturing modbusTCP packets, while with LaptopC (personal laptop) it also captures modbusTCP packets correctly. When I don't use switch port in mirror mode i.e. I just want to monitor packets running through the laptop (generating traffic with a modbusTCP simulated server for example, or a PLC project platform) ethernet port, it catches them correctly with all my three laptops. So, anyone has any idea about what maybe hidden setting may affect the two company laptop such a way that they miss the modbusTCP packets only while in "sniffing" mode? Thanks

ModbusTCP capture not working on certain Laptops

Good morning, morning,

I am finding a strange problem and my company IT guy cannot figure out too. too.

For a test I have three laptops running wireshark, installed absolutely the same way (default setting, full install, same version): -LaptopA=company version):

  • LaptopA=company laptop, windows 11 -LaptopB=company laptop, windows 10 -LaptopC=personal 11
  • LaptopB=company laptop, windows 10

  • LaptopC=personal laptop, windows 10

When I capture packets from a mirror port of a switch or of a PLC, with LaptopsA&B (the company laptops) it captures all but fails capturing modbusTCP packets, while with LaptopC (personal laptop) it also captures modbusTCP packets correctly. correctly.

When I don't use switch port in mirror mode i.e. I just want to monitor packets running through the laptop (generating traffic with a modbusTCP simulated server for example, or a PLC project platform) ethernet port, it catches them correctly with all my three laptops. laptops.

So, anyone has any idea about what maybe hidden setting may affect the two company laptop such a way that they miss the modbusTCP packets only while in "sniffing" mode? Thanks Thanks