Re: Proposal: Incremental Backup

Il 12/08/14 15:25, Claudio Freire ha scritto:
> On Tue, Aug 12, 2014 at 6:41 AM, Marco Nenciarini
> <marco.nenciarini@2ndquadrant.it> wrote:
>> To declared two files identical they must have same size,
>> same mtime and same *checksum*.
>
> Still not safe. Checksum collisions do happen, especially in big data sets.
>

IMHO it is still good-enough. We are not trying to protect from a
malicious attack, we are using it to protect against some *casual* event.

Even cosmic rays have a not null probability of corrupting your database
in a not-noticeable way. And you can probably notice it better with a
checksum than with a LSN :-)

Given that, I think that whatever solution we choose, we should includechecksums in it.

Regards,
Marco

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Marco Nenciarini - 2ndQuadrant Italy
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