If you have ever fired up a Cisco router in , GNS3 , EVE-NG , or Cisco Packet Tracer , you have likely seen the console output slowly crawl by until it halts at a seemingly concerning line:
, a technology that allows a virtual machine to use the host's printers. When VMware can't find the necessary driver on the host or the feature is turned off in the main preferences, it alerts you that the device won't be active during the session [ Are you currently using a
Some VM templates or quick-creation wizards add a serial port by default but leave it disconnected. This is common in Linux VM templates that include a legacy console serial port that may not be needed. virtual device serial0 will start disconnected
: Once your physical connectivity and DCE/DTE relationships are set, ensure you run the no shutdown command on the interface from Cisco IOS, or the interface will remain in an "administratively down" state.
for the VM and remove the Serial Port device entirely to stop the log warning. Why is this happening? If you have ever fired up a Cisco
Full log example:
Starting with VMware Fusion 13.5 and Workstation 17.5 , VMware officially retired , a legacy technology that mapped printers via a virtual serial port (serial0). Because the software no longer supports the "thinprint" file type, it flags it as an invalid value and tells you the device will start disconnected. : Once your physical connectivity and DCE/DTE relationships
: Similar errors can happen with network cards (Ethernet0) if there is a vLAN name case mismatch (e.g., "VLAN1" vs "Vlan1") or a race condition during a vMotion migration.
Select a valid COM port from the dropdown menu (e.g., COM1). Use file: Direct the output to a text file on your host.
This message typically appears in virtual machine platforms (like , VirtualBox , or QEMU ) or network simulation tools (like GNS3 or EVE-NG ).
: The message may appear if you have not properly installed the correct WIC (e.g., a WIC-2T for serial ports) into the router's slot before linking devices. GNS3 will not recognize a serial interface if the underlying hardware module is not present in the router's configuration.