Re: Need help to recover root filesystem after a power supply issue

Carlos E. R.
2019-07-11T10:23:48Z

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On 11/07/2019 09.10, Andrey Zhunev wrote:
>
> Thursday, July 11, 2019, 5:47:36 AM, you wrote:

...

>>> So I wiped them with hdparm:
>>> # hdparm --yes-i-know-what-i-am-doing --write-sector <sector_number> /dev/sda
>
>> This has always eluded me. How did you know the sector numbers?
>
>
> When you use ddrescue (or any other tool) to try and read the data
> and there is a read error, an error message is added to your kernel
> log. You can find the sector number there:

Ah, ok, yes, I see. Thanks :-)

...

>>> I then re-read all these sectors, and they were all read correctly.
>>>
>>> The number of pending sectors reported by SMART dropped down to 7.
>>> Interestingly, there are still NO reallocated sectors reported.
>
>> I suspect that the figure SMART reports only starts to rise after some
>> unknown amount of sectors have been remapped, so when the numbers
>> actually appear there, it is serious.
>
> Hmmm, this is an interesting thought!
> Everybody lies... :)

It is either that, or the number has a multiplier, and starts counting
at one hundred, two hundred... I don't know.

--
Cheers / Saludos,

Carlos E. R.
(from 15.0 x86_64 at Telcontar)

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