Grub confusion

[Sarunas Burdulis]

On 12/11/2013 01:32 AM, Kevin O'Gorman wrote:
> On Tue, Dec 10, 2013 at 6:56 AM, Jim Byrnes <jf_byrnes at comcast.net> wrote:
>> On 12/09/2013 09:27 PM, Kevin O'Gorman wrote:
>>>
>>> Running xubuntu 13.04, I have 4 large hard drives on the machine, some
>>> of which have been used before as boot drives.
>>>
>>> The BIOS tries to use the first one that it can access that also
>>> contains a bootstrap loader.  I would like to remove the loaders, but
>>> maintain the partition table in all drives but one.
>>>
>>> Is there a handy way to do this?
>>>
>>
>> Does your bios/efi maybe allow you to specify the hard drive to boot from?
>> Mine does and it made swapping out a HD with Ubuntu on it for one with Win 7
>> and still boot from a remaining HD with a different copy of Ubuntu on it.
>>
>> Regards,  Jim
> 
> All drives are MBR formatted.
> 
> I described the situation poorly, reflecting the fact that I'm both
> frustrated and confused.  The 4 drives are the same make and model, so
> the BIOS can't tell me which one is which.  The mobo has 6 internal
> SATA-3 connectors, in a group of 2 and another group of 4, with no
> obvious order.

There might be markers on the motherboard next to SATA ports, and the
order should be sequential from SATA-0 to SATA-5, most likely
left-to-right. Motherboard's user's manual (usually available as PDF
from manufacturer's website) might have some clarifying info as well.
Running

sudo dmidecode --type baseboard

should give motherboard info, if needed.

In addition to drive model names BIOS will often also list serial
numbers of drives attached. From OS you can check drive serial numbers
and associate them with /dev/sd? by using, for example

sudo hdparm -i /dev/sda

or

sudo smartctl -i /dev/sda
(from smartmontools package)

'sudo blkid' might also add some clarity in your situation.

-- 
Sarunas Burdulis

http://math.dartmouth.edu/~sarunas