[Discuss] Advice: Best approach to data recovery from failed LINUX ext4 Hard Drive

[BCLUG]

Craig Miller wrote on 2022-08-14 07:42:

> First thing to do is us 'dd' to make a copy of the affected hard 
> drive. Then attempt recovery on the dd image. If the recovery on the 
> image goes badly, you still have the original.

I'd suggest dd-rescue: it's dd with some intelligence, in that it logs
which sectors were successful, and it'll dump as much data as possible
then come back to the bad sectors and re-try them.


> GNU ddrescue is a data recovery tool for disk drives, CD-ROMs, and 
> other digital storage media. It copies raw blocks of storage, such
> as disk sectors, from one device or file to another, while handling
> read errors in an intelligent manner to minimize data loss by
> scraping good sectors from partially read blocks.

> ddrescue uses a sophisticated algorithm to copy data from disk
> drives, and other storage devices, causing as little additional
> damage, if they are failing, as possible.[2] It is considered to have
> the most sophisticated implementation of a block-size-changing
> algorithm in free and open source software,[3][4] and is considered
> an essential data recovery tool.[5][6]


https://en.wikipedia.org/wiki/Ddrescue