Actions
Forum Thread Details
  • Replies 29 replies
  • Subscribers 288 subscribers
  • Views 894 views
  • Users 0 members are here
Related

E14 Community recommendation for ModBus TCP client

colporteur

I am looking for an application to query a ModBus TCP interface on a scale head?

image

The company I am working for has recently installed a RiceLake 1280 scale indicator with a Modbus TCP interface. The scale indicator is IP capable and resides in a network DMZ. The goal is to have a cloud vendor pull scale data over the network from the Modbus interface. I'm looking for an application that can query the Modbus interface to confirm communication with the interface. 

The scale vendor recommended an application in order to set the Modbus TCP interface IP address. I managed to get that working, proving the interface IP answers an IP ping. DMZ rules have been set in place to isolate the indicator. I want to test that the cloud vendor can get to the Modbus interface and pull the data. I'm thinking maybe there is a software tool like minicom is for serial communication, except the tool is for Modbus.

E14 has some great Modbus resources but nothing to match my search. A Modbus client query tool. I'm hoping there is a community member that has experience with Modbus TCP and that they could recommend application software to perform the task.

Parents

  • So, to get this clear, you have set up rules that allow an computer out of your control to enter your DMZ and connect to your scale?

    I find this quite dangerous security wise, I would have done it the other way around, with an internal computer talking to the scale, retrieving the values and pushing those to the cloud provider.

    But if you want to test the connection, you can do it with a telnet client, provided you know the port it is listening to. I mean you won't be able to "talk" the right application layer protocol, but at least you'll see if the connection goes through.

    Try first from inside the DMZ, then use a computer from outside (your phone via 4G?) to see if you can still connect. Then, you can hand over the "package" to the cloud vendor who should be able to do the same while knowing which application layer protocol to use and get the proper data out of your scale.

    But once again, I find it quite dangerous to let a third party directly access a machine inside your own organization.

  • in reply to obones

    If, if, if, if my aunt was a man she would be my uncle.

    There is a trust in the vendor through a VPN tunnel. There is less trust for the scale indicator in the network.

    I never thought of telnet'ing to the interface. I never think of the protocol since it was replaced by ssh. I will give it a try.

  • in reply to colporteur

    In general, it is not a great approach to trust the vendor, or anyone else. You might think you trust the vendor itself, but if they get compromised, you get compromised too. You need to minimize your attack surface and trust the absolute least number of entities possible. In your setup, it sounds like there's zero reason for you to ever give access to anything for anyone, and you should be sending data to the vendor instead of them pulling data. Obviously, I don't know your exact constraints or setup, there might be a valid reason to do what you are doing, but consider this carefully.

  • in reply to colporteur

    Well, telnet will tell you if the connection can be established, which is a first "layer" of tests.

    After that, a quick search for modbus TCP lead me to this reddit with a few suggestions: https://www.reddit.com/r/PLC/comments/ncp724/modbus_tcp_computer_client/?show=original

Reply Children
No Data