Re: Recover array after I panicked

["Patrik Dahlström" <risca@powerlamerz.org>]

On 04/23/2017 04:06 PM, Brad Campbell wrote:
> On 23/04/17 17:47, Patrik Dahlström wrote:
>> Hello,
>>
>> Here's the story:
>>
>> I started with a 5x6 TB raid5 array. I added another 6 TB drive and
>> started to grow the array. However, one of my SATA cables were bad and
>> the reshape gave me lots of I/O errors.
>>
>> Instead of fixing the SATA cable issue directly, I shutdown the server
>> and swapped places of 2 drives. My reasoning was that putting the new
>> drive in a good slot would reduce the I/O errors. Bad move, I know. I
>> tried a few commands but was not able to continue the reshape.
>>
> 
> Nobody seems to have mentioned the reshape issue. What sort of reshape
> were you running? How far into the reshape did it get? Do you have any
> logs of the errors (which might at least indicate whereabouts in the
> array things were before you pushed it over the edge)?
These were the grow commands I ran:
mdadm --add /dev/md1 /dev/sdf
mdadm --grow --raid-devices=6 /dev/md1

It got to roughly 15-17 % before I decided that the I/O errors were more
scary than stopping the reshape.
> 
> 
> What you'll have is one part of the array in one configuration, the
> remaining part in another and no record of where that split begins.
Like I said, ~15-17 % into the reshape.
> 
> Regards,
> Brad