ModbusPal runing problem on Ubuntu 20.04

# 2 months ago
Ding	Hi, I'm not sure if I should put the question here, but it is related to Tango, so maybe someone happened to experience it before. I installed ModbusPal(ver.1.6b,Modbus simulator) on a real Ubuntu/20.04 as it is on the VirtualBox9.3. However, after clicking on the "Run" button on the screen of ModbusPal, all buttons "die", the only thing I could do is to kill the ModbusPal on the terminal. I also tried ModbusPal(Ver.1.6c), the case is the same except it shows on the terminal :"Could not load initial port number. Loading defaut port number". It looks the ModbusPal failed to open the default port 502. Following is what action I took on this: 1) I use the super user command " sudo java -jar ModbusPal.jar" to start the ModbusPal. 2) The firewall on ubuntu is inactive, 3) The SElinux is stopped. 4) "sudo ss -ntlp \| grep LISTEN" shows that the port 502 is not taken by other application. 5) OS: Unbuntu/20.04, Java version:1.8.0_392, Modbupal ver.1.6b and 1.6c. I did a lot of research on this issue, but still don't have any clue, so is there any body happened to experience this issue? Thanks Ding Edited 2 months ago

# 2 months ago

Hi,

I'm not sure if I should put the question here, but it is related to Tango, so maybe someone happened to experience it before.

I installed ModbusPal(ver.1.6b,Modbus simulator) on a real Ubuntu/20.04 as it is on the VirtualBox9.3. However, after clicking on the "Run" button on the screen of ModbusPal, all buttons "die", the only thing I could do is to kill the ModbusPal on the terminal. I also tried ModbusPal(Ver.1.6c), the case is the same except it shows on the terminal :"Could not load initial port number. Loading defaut port number".

It looks the ModbusPal failed to open the default port 502. Following is what action I took on this:
1) I use the super user command " sudo java -jar ModbusPal.jar" to start the ModbusPal.
2) The firewall on ubuntu is inactive,
3) The SElinux is stopped.
4) "sudo ss -ntlp | grep LISTEN" shows that the port 502 is not taken by other application.
5) OS: Unbuntu/20.04, Java version:1.8.0_392, Modbupal ver.1.6b and 1.6c.

I did a lot of research on this issue, but still don't have any clue, so is there any body happened to experience this issue?

Thanks
Ding

Edited 2 months ago

# 2 months ago
Reynald	Hi Ding, This does not look like a Tango related issue. Maybe you can try to get some help directly from ModbusPal project? https://sourceforge.net/p/modbuspal/discussion/899955/ Kind regards, Reynald Rosenberg's Law: Software is easy to make, except when you want it to do something new. Corollary: The only software that's worth making is software that does something new.

# 1 month ago
Ding	Reynald Hi Ding, This does not look like a Tango related issue. Maybe you can try to get some help directly from ModbusPal project? https://sourceforge.net/p/modbuspal/discussion/899955/ Kind regards, Reynald Hi Reynal, Thank you for the help. Yes, you are right, it has nothing to do with Tango, and it actually is the issue of ModbusPal with Linux. I just tried to replica the Tango demo of VirtualBox 9.3, where the ModbusPal runs well. I'll seek help from ModbusPal website and see the result. Regards, Ding

# 1 month ago

Ding

Reynald
Hi Ding,

This does not look like a Tango related issue.
Maybe you can try to get some help directly from ModbusPal project?
https://sourceforge.net/p/modbuspal/discussion/899955/

Kind regards,
Reynald

Hi Reynal,

Thank you for the help. Yes, you are right, it has nothing to do with Tango, and it actually is the issue of ModbusPal with Linux. I just tried to replica the Tango demo of VirtualBox 9.3, where the ModbusPal runs well. I'll seek help from ModbusPal website and see the result.

Regards,
Ding