Re: Re: BUG #5602: Recovering from Hot-Standby file backup leads to the currupted indexes

On Thu, 2010-08-12 at 01:31 -0400, Tom Lane wrote:
> So the DBA is
> just flying blind as to whether the slave is trustworthy yet.  I can't
> prove that that's what burnt the original complainant, but it fits the
> symptoms.

The safest approach is to

1. run pg_start_backup() on master, remember LSN
2. copy backup_label from master to standby
3. wait for starting LSN to be applied on standby
4. run backup on standby
5. run pg_stop_backup() on master

That ensures we don't run without full page writes during backup and
that we have an explicit consistency point to work from.

--
 Simon Riggs           www.2ndQuadrant.com
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