Virtual Device Serial0 Will Start Disconnected

For advanced users or headless ESXi environments, you can fix this issue directly within the virtual machine configuration file.

When you encounter the message "Virtual device serial0 will start disconnected," it typically occurs in the context of virtualization software, such as VMware, VirtualBox, or Hyper-V. This message pertains to the configuration and behavior of a virtual serial port (often referred to as serial0 ) within a virtual machine (VM). Let's explore what this means, the reasons behind it, and the implications for your virtual environment.

If you actually need to use a serial port and the error says "no corresponding device available on the host," try these steps:

If you want to keep the serial port configuration for future use but stop the boot-time warning, you can tell the hypervisor not to initialize it during startup. Open the virtual machine . Select the Serial Port device. virtual device serial0 will start disconnected

Alternatively, to completely remove it, click the button at the bottom of the window. Click OK to save changes and power on the VM. For VMware ESXi / vSphere Web Client: Log into your vSphere Client or ESXi host client interface.

Are you using this serial port for or just trying to get a clean boot ?

For debugging, named pipes offer low latency and are ideal for VM‑to‑VM communication. For remote access across physical locations, TCP network connections are appropriate. For logging crash information, file‑based serial ports (stored on a datastore) provide reliable storage. For advanced users or headless ESXi environments, you

If you want to keep the device for occasional use but stop the error message at startup: Go to . Select the Serial Port hardware. Uncheck the box for "Connect at power on" .

On Windows, right‑click the VMware Workstation icon and select Run as administrator to ensure VMware has the necessary permissions to access the hardware ports.

Alternatively, if you want the device present but disconnected at boot time, edit the file to read: serial0.present = "TRUE" serial0.startConnected = "FALSE" Use code with caution. Let's explore what this means, the reasons behind

Emulating network switches and routers (e.g., Cisco IOS images via GNS3) that utilize virtual serial interfaces for console access.

Locate the folder where your VM files are stored and find the file. Open it with a text editor (like Notepad). Find and delete the following lines: serial0.fileType = "thinprint" serial0.fileName = "thinprint" serial0.present = "TRUE" Save the file and restart the VM. Method 3: Disable "Connect at Power On"