I have currently no way to test this myself, but since we are based on Debian, you can probably use the same tutorials for enabling a serial console.
Here's what I've found, hope this helps:
My problem is more understanding how to say to proxmox things said with standard qemu interface.
I need a serial port implemented via telnet, which can be said with standard qemu like -serial telnet... and I don't know :
- how to say the same thing being in proxmox
- how exactly is implemented the qm command : qm terminal; perhaps I can use some way using it, if I know more about it.
I’ve recently done this setup on Windows using a serial-to-TCP redirector.
What I did was map my COM port to a local TCP port, so the serial data is forwarded over the network. Then I connected with PuTTY in Telnet mode to that port, and it behaved just like a normal serial connection from the application side.
I followed an approach like this: https://www.serial-over-ethernet.com/features/redirect-serial-port-to-telnet/
In my case I selected the COM port, assigned a TCP port, started the redirector and then connected to it from PuTTY.
Sorry for replying to an old thread but I thought this might still be useful to someone.