dd - cloning a disk.

[Joseph Vella]

On Saturday 11 March 2006 14:43, Wojciech Puchar wrote:
> >
> > Here is a simple (I think!) question for the I/O savy among you:
> >
> > If I had two identical disks, say, 73 GB Seagate 10K SCSIs, one completely 
> > operational fully setup FreeBSD with all the trimmings, and the other 
blank, 
> > or perhaps loaded but no longer usable, is 'dd' and appropriate tool to 
> > completely clone the Good disk to the not so good disk....therefor making 
the 
> > second disk identical to the first? Bootable and all?
> 
> yes
> 
> dd if=/dev/firstdisk of=/dev/seconddisk bs=64k
> 
> and yes it is bootable, but if you boot from second disk, FreeBSD kernel 
> will mount root from first disk anyway, unless you will reconfigure it.
> 

Would this also work to copy CDs?  If so, does it matter what os and/or format 
they would have?