# Re: \[RFE\] Please, add optional RAID1 feature (= chunk checksums) to make it more robust

- From: Mathias Burén \<hidden\>
- Date: 2012-07-18 11:13:09 
- List: linux-raid
- Page: https://ratatoskr.run/linux-raid/2012/07/6621112
- Thread: https://ratatoskr.run/linux-raid/2012/07/6621111/t.md

```text
On 18 July 2012 12:01, Jaromir Capik [ref] wrote:
> Hello.
>
> I'd like to ask you to implement the following ...
>
> The current RAID1 solution is not robust enough to protect the data
> against random data corruptions. Such corruptions usually happen
> when an unreadable sector is found by the drive's electronics
> and when the drive's trying to reallocate the sector to the spare area.
> There's no guarantee that the reallocated data will always match
> the original stored data since the drive sometimes can't read the data
> correctly even with several retries. That unfortunately completely masks
> the issue, because the sector can be read by the OS without problems
> even if it doesn't contain correct data. Would it be possible
> to implement chunk checksums to avoid such data corruptions?
> If a corrupted chunk is encountered, it would be taken from the second
> drive and immediately synced back. This would have a small performance
> and capacity impact (1 sector per chunk to minimize performance impact
> caused by unaligned granularity = 0.78% of the capacity with 64k chunks).
>
> Please, let me know if you find my request reasonable or not.
>
> Thanks in advance.
>
> Regards,
> Jaromir.
>
> --
> Jaromir Capik
> Red Hat Czech, s.r.o.
> Software Engineer / BaseOS
>
> Email: jcapik@redhat.com
> Web: www.cz.redhat.com
> Red Hat Czech s.r.o., Purkynova 99/71, 612 45, Brno, Czech Republic
> IC: 27690016
>
>
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That would be a disk format change...

Why not use btrfs or zfs?

Mathias
```