Re: Backup Strategy Advise

On 04/24/2018 07:50 AM, David Gauthier wrote:
> Hi:  I need some advise on how best to backup a PG DB.
> PG 9.5.2 on RHEL6
>
> The requirement is to be able to restore the DB after catastrophic
> failure and lose no more than the last 15 minutes worth of data.  Also,
> we would like to be able to do the backups on-line (no down time).
> There is no need for PITR other than the point in time being the latest
> possible.
>
> Typically, I would think doing a weekly full backup, daily incremental
> backups and turn on journaling to capture what goes on since the last
> backup.  When DB recovery is needed, restore up to the last daily, then
> reply the journal to restore up to the last time the journal was flushed
> to disk (checkpoint=15 minutes).  I'm not quite sure if something like
> this is possible with PG.  I've read about the WAL file and wonder if it

Pretty sure that won't work. Once you do the restore from the last daily
you will change the Postgres files to a state different from the ones
captured by the journaling. Replaying the journal will result in a
mixture of old and new.

> could be used together with the on-line logical backups (pg_dump) to
> achieve the 15 minute requirement without needing downtime for physical
> backups..
>
> Any advise?

Take a look here:

https://www.postgresql.org/docs/9.5/static/continuous-archiving.html

>
> Thanks in Advance.

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com