Virtual Device Serial0 Will Start Disconnected -

Many Linux appliances (like Kali Linux, Ubuntu Server, or network firewalls like pfSense) are pre-configured with serial ports because they are often used in headless server environments where admins manage them via text commands over a serial connection.

If you add a serial port to a VM but do not specify what it connects to (e.g., a physical COM port, a file, a named pipe, or an output to a printer), VMware will default to disconnecting it. The device is present but inactive.

If you need serial0 active at boot:

The warning appears in:

Full log example:

2025-11-10T14:23:18.456Z| vmx| I125: Serial0: file type is device
2025-11-10T14:23:18.456Z| vmx| W110: Virtual device serial0 will start disconnected.
2025-11-10T14:23:18.456Z| vmx| I125: Serial0: No physical serial port autodetected.

The W110 denotes a warning, not an error.

Q: Does this warning affect clone or snapshot operations?
A: No. Snapshots and clones remain unaffected. The disconnected serial port does not hold any state. virtual device serial0 will start disconnected

Q: Can I hide the warning without removing the serial port?
A: In VMware Workstation, you cannot suppress warnings globally. The only way is to connect the port to a valid target (file or pipe) or remove it.

Q: Does this appear in VirtualBox or Hyper-V?
A: VirtualBox calls it "Serial Port 1 – disconnected" and Hyper-V shows no explicit warning unless you open guest settings. The behavior is VMware-specific in phrasing but functionally similar. Many Linux appliances (like Kali Linux, Ubuntu Server,

Q: What if I have multiple serial ports (serial1, serial2)?
A: The same rule applies. Each disconnected port will log a separate warning.