raptor310,

In older kernels dd always displays the prompt on completion. This is to say dd accepts the command, executes it and shows nothing if the operation is successful.

One can get some sense of the progress by issuing a "date" statement before and after the dd command. The first "date" command shows the time before dd is executed but the second "date" command will not produce any display until after the completion of the dd command. Thus if the second "date" output is displayed the difference between the two shows the time it has taken to carry out the cloning.

On newer kernel dd actually reports the time it took to complete the task.

The time it takes is also easily estimated. Internal to internal disks cloning will get a throughput of between 40 to 60Mb/s, depending on the type of hard disk and CPU. If one of the disk is attached to a USB port then the speed will cut back to about 10 to 12 Mb/s.