Skip to content

Managing VM Disks

This guide explains the functions of the buttons available in the "Disks" tab.

Add Disk

This button allows you to create a brand new virtual disk and attach it to the VM.

  • You will be prompted to select a Storage Pool where the new disk image file will be created.
  • You must provide a Volume Name for the new disk (e.g., new-data-disk.qcow2).
  • You must specify its Size and Format (qcow2 or raw).
  • The VM does not need to be stopped to add a new disk.

Attach Existing Disk

This attaches a pre-existing disk image to your VM. This is useful if you have an existing .qcow2, .raw, or .iso file you want to use.

  • The system will first ask you to select a Storage Pool that contains the disk volume you want to attach.
  • If the disk file is not part of a libvirt storage pool yet, you should first use the "Attach" button in the Server Preferences -> Storage tab to make it known to libvirt. This might involve creating a new storage pool for the directory containing your disk file.

Edit Disk

(This button is enabled only when a disk is selected in the table)

Allows you to modify properties of an attached disk, such as: - Bus Type: virtio, sata, scsi, etc. - Cache Mode: none, writeback, etc. - Discard Mode: unmap, ignore.

Important: The VM must be stopped to edit disk properties.

Remove Disk

(This button is enabled only when a disk is selected)

This detaches the selected disk from the virtual machine.

  • This action does NOT delete the disk image file. The file remains in its storage pool or on your filesystem.
  • It only removes the disk from this specific VM's configuration.
  • The VM must be stopped to remove most types of disks.

Disable Disk

(This button is enabled for active disks)

This temporarily "unplugs" the disk from the VM without removing its configuration.

  • The disk will become invisible to the guest operating system but remains in the disk list with a (disabled) status.
  • This is useful for troubleshooting or temporarily preventing access to a disk without fully removing it.

Enable Disk

(This button is enabled for disabled disks)

This "re-plugs" a disabled disk back into the VM, making it available to the guest operating system again.