Re: Condition to become the standby mode.

On 2013-07-26 23:47:59 +0900, Fujii Masao wrote:
> >> If this problem is solved, there is possible of that we can failback
> >> by removing the all WAL record which is in pg_xlog before server
> >> starts as the slave server.
> >> ( And we also use "synchronous_transfer" which I'm proposing, I think
> >> we can fail-back without taking full backup surely)
> >
> > I still have *massive* doubts about the concept. But anyway, if you want
> > to do so, you should generate a backup label that specifies the startup
> > location.
> 
> Generating a backup label doesn't seem to be enough because there is
> no backup-end WAL record and we cannot know the consistency point.

Since 9.2 we allow generation of base backups from standbys, the
infrastructure built for should be sufficient to pass the lsn at which
consistency is achieved.

Greetings,

Andres Freund

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