Re: PG backup check

On Tue, Jul 17, 2018 at 11:17 AM, Guillaume Lelarge <guillaume(at)lelarge(dot)info>
wrote:

> 2018-07-17 2:35 GMT+02:00 Ravi Krishna <sravikrishna3(at)gmail(dot)com>:
>
>> Not sure I am following this. Did Google release this because PG backups
>> are not 100% reliable or the data corruption can occur due to hardware
>> failure.
>>
>> http://www.eweek.com/cloud/google-releases-open-source-tool-
>> that-checks-postgres-backup-integrity?utm_medium=email&
>> utm_campaign=EWK_NL_EP_20180713_STR5L2&dni=450493554&rni=24844166
>>
>
> From what I understand with this Google tool, it has nothing to do with
> backups. It just allows you to check data blocks in a PostgreSQL cluster.
> Google advice is to run it before taking a backup, but that's about it.
>
>
This appears to basically be the same tool that's already included in
PostgreSQL 11, and has been around in a few different incarnations (but
unpolished) for years.

FWIW, in relation to backups, tools like pgbackrest already did this
transparently during backup, and again PostgreSQL 11 will do it built-in.

It's quite possible Google was running this internally before of course,
and a separate tool from others, but it's not exactly news... But they do
outline a very definite problem, which is that if you get physical
corruption in your database, it gets included in the backups. And if it's
in a portion of the database you don't use a lot, checksum failures won't
be noticed until you actually try, which is way too late.

--
Magnus Hagander
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