HPA and dmraid

[Anthony Blakemore]

  On 08/02/2011 20:09, Phillip Susi wrote:
> You should always set a subject when sending email.
Yes sorry, i had to use a friends box with ff4 thats not playing nice 
with m$ live mail. I had to paste my message and hit send before the 
page refreshed again.
> On 2/5/2011 11:19 PM, Anthony B wrote:
>
>> ata1.00: HPA unlocked: 976771055 ->  976773168, native 976773168
> Unfortunately when the libata transition happened, Ubuntu decided to
> unlock the HPA by default, because there was a bug in the old ide driver
> that did the same.  Some work has been under way lately to correct this
> issue upstream by having the kernel only unlock the HPA automatically if
> it is required to access a defined partition.
>
That would have saved me a lot of trouble. I was about to dd /dev/zero 
to both disks and start over again but knowing what i do now, that still 
would not have worked.
>> Nice, everything has fallen into place now. I know why my disk would
>> only be detected as part of the array after power cycling and why
>> dmraid wouldn't detect it but, my array is broken and i want ALL my
>> bytes back. All i have to do is re-enable hpa at the right place to
>> get the raid working again and tell the kernel at boot not to mess
>> with hpa. But like i say MY BYTES AND I WANT THEM BACK.
> Yep, that's what you need to do.
>
Once i'd figured out the nvidia raid metadata was written to the second 
to last sector, i re-enabled hpa to the position in the log, set kernel 
command "libata.ignore_hpa=0", dd'd the last two sectors to a file, then 
dd'd it back on with hpa unset. Now both os'es are happy and so am i.