APU2C4 and pfsense NUT package cannot detect USB UPS when serial cable is connected

[kevindd992002]

For the APU2C4, why is it that when I have a serial cable connected between its serial port and a computer, its USB ports don't work? I have a UPS plugged in to one of its USB ports and I use the NUT package in pfsense. As soon as I connect to the hardware through the serial port (using putty), the USB port does not work. Unplugging the serial cable fixes the issue and that's why I know it's the one causing it. This is happening for both of my APU2C4 boxes.

When I connect the serial cable, I get these messages:

[kevindd992002]

@miczyg1 do you have ideas here?

[macpijan]

@kevindd992002 Does it also happen with different USB devices (let's say USB stick instead of UPS), so we can have easier time trying to reproduce it?

Have you tried different OS, or the pfsense only?

In our test units we always have the serial cables connected, and we do use the USB all the time, so I'm sure we would have spotted that issue.

Which firmware version are you using?

[kevindd992002]

No, it doesn't affect other USB devices, only the UPS (APC BR1500GI, to be specific). Here are my latest tests about the issue:

https://forum.netgate.com/post/994064

I also have a coupe of posts before and after the post discussing this issue with the community there.

I haven't tried different OS with this box as it's my main pfsense router/firewall.

That's what I thought. You would've caught that easily if it was really a problem. At this point, I'm thinking it's because I'm using a cheap usb-to-serial cable but I can's say for sure.

I'm at v4.14.0.2