Enabling Com Port on Hyper-V 2nd Generation VM / Windbg

To test the UEFI boot environment, I created a second generation virtual machine in Hyper-V. And I had to configure the Com port to attach the kernel debugger. However, the Com Port device was not visible in the 2nd generation Hyper-V VM. 
Invisible Com port device
Hyper-V 2nd generation VM must be assigned a pipe to the Com port to be visible in the device list.

1. VM termination

First, shut down the VM before working.

2. Run as Powrshell administrator

Detailed configuration of Hyper-V VM can be done through Powershell command. Run Powershell with administrator privileges. 

3. set-vmcomport 

Run the following command to activate the com port.
set-vmcomport -vmname [VM이름] -number [COM포트번호] [파이프이름]
To check the COM port to which the pipe is assigned, execute the following command.
get-vmcomport -vmname [VM이름]
The following is an example of command execution. 

 
Set-VMComPort (hyper-v)
Use this topic to help manage Windows and Windows Server technologies with Windows PowerShell.
docs.microsoft.com

4. Run VM

If you look at the device manager, you can see that the com port is activated.

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