Enable Serial Terminal for Ubuntu/Linux VM

Enabling a serial terminal for Ubuntu or Linux VMs allows you to access the VM console via a serial port, which is supported by most hypervisors (Proxmox, VMware, VirtualBox, etc.). This guide walks you through the process.

Prerequisites

A hypervisor (Proxmox, VMware, VirtualBox, etc.) with an Ubuntu/Linux VM
Access to the VM via SSH or Console

Steps

1. Add a Virtual Serial Port

Open your hypervisor's management interface.
Select your VM.
Add a Serial Port to the VM hardware.
Confirm and restart the VM if required.

2. Enable Serial Console in Ubuntu/Linux

Log in to your Ubuntu/Linux VM (via SSH or Console).
Enable and start the serial-getty service for the serial port (usually ttyS0):
```
sudo systemctl enable serial-getty@ttyS0.service
sudo systemctl start serial-getty@ttyS0.service
```
info
Single command alternative:
sudo systemctl enable --now serial-getty@ttyS0.service
If your serial port uses a different device (e.g., ttyS1), adjust the command accordingly.

3. Access the Serial Terminal

Use your hypervisor's console feature (e.g., xterm.js in Proxmox, Serial Console in VMware/VirtualBox).
You should now see the Ubuntu/Linux login prompt via the serial terminal.

Example: Proxmox VE

If you are using Proxmox VE, follow these steps:

Open the Proxmox Web GUI.
Select your VM.
Go to Hardware.
Click Add → Serial Port.
Confirm and restart the VM.
After enabling the serial-getty service as described above, go to Console and select xterm.js.
You should see the Ubuntu/Linux login prompt via the serial terminal.

Prerequisites​

Steps​

1. Add a Virtual Serial Port​

2. Enable Serial Console in Ubuntu/Linux​

3. Access the Serial Terminal​

Example: Proxmox VE​