Add Virtual Disk in Hyper-V without Shutdown
In Hyper-V, there are some instances where it is necessary or needed to add additional virtual hard drives (VHD) to a virtual machine (VM) without shutdown. The follow are the steps on how to do so.
Select the VM that you want to add the VHD, right click>settings:
Select SCSI Controller>Hard Drive, then click Add.
Select the disk type (recommend fix size) and click Next.
Type the name of the new VHD and click Next.
Choose the size of the new VHD and click Next.
Click Finish to create the new VHD.
Click OK to close out the settings menu for the VM.
Login to the VM, go to Disk Management, and bring the new VHD online.