Hi Arman,
VM's migration and disks migration are two different things:
- Live storage migration:
A VM's disk can be moved to another storage domain while the VM is running, by copying the disk's structure the destination domain.
The hard part of live storage migration is moving the active layer
volumes from one domain to another, while the VM is writing to those
volumes.
By using a replication operation, the data is written to both source and destination volumes.
When both volumes contain the same
data, the block job operation can be aborted, pivoting to the new disk.
- Live migration:
Provides the ability to move a running virtual machine between physical
hosts with no interruption to service.
The virtual machine remains
powered on and user applications continue to run while the virtual
machine is relocated to a new physical host.
A running virtual machine can be live migrated to any host within its
designated host cluster.
Live migration of virtual machines does not
cause any service interruption.
Hope it helps!