dd to clone disks - new disk fails to boot.

Warren Block wblock at wonkity.com
Wed Oct 20 13:55:13 UTC 2010

On Wed, 20 Oct 2010, Modulok wrote:

> Problem: I copied from an old hard drive to a new one via FreeBSD's
> dd. The new drive won't boot. The old drive worked fine. (The new
> drive is known-to-work.)
> Background: I have a system with a 160GB disk in it. It runs windows.
> It works. I have a blank 250GB disk. I want to copy the entire 160GB
> disk onto the 250GB disk, shuffle the SATA cables and boot to it.
> Basically, I'm just replacing the small hard drive with a larger one.
> I would then extend the partition using something like gpartd.
> I booted to a live FreeBSD disk and used dd like so:
>    dd if=/dev/ad4 of=/dev/ad8 bs=1m
> About an hour later it finished. No errors. I turned the machine off,
> unplugged the small disk and connected the big disk into the primary
> SATA header. The BIOS chokes on the new disk. It refuses to boot from
> it and instead reports 'disk error'.

If the BIOS is complaining, see if the new drive has a SATA 150 jumper, 
or some other compatibility mode.

More information about the freebsd-questions mailing list