A number of specific virtual machine configurations can prevent migration of a virtual machine with vMotion.

The following virtual machine configurations can prevent migration with vMotion:

You cannot use migration with vMotion to migrate virtual machines using raw disks for clustering purposes.

You cannot use migration with vMotion to migrate a virtual machine that uses a virtual device backed by a device that is not accessible on the destination host. (For example, you cannot migrate a virtual machine with a CD drive backed by the physical CD drive on the source host.) Disconnect these devices before migrating the virtual machine.

Virtual machines with USB passthrough devices can be migrated with vMotion as long as the devices are enabled for vMotion.

You cannot use migration with vMotion to migrate a virtual machine that uses a virtual device backed by a device on the client computer. Disconnect these devices before migrating the virtual machine.