Re: BUG #15331: Please check if recovery.conf can be renamed

On 2018-08-16 20:50:55 +0900, Michael Paquier wrote:
> On Thu, Aug 16, 2018 at 11:30:09AM +0000, PG Bug reporting form wrote:
> > This means that promotion fails, and for me even after fixing the
> > permissions the system was in an odd state that took some work to fix.
> > Failover is hard to get right; emitting a warning earlier in this case would
> > mean one less thing to go wrong.
>
> I think that you would be interested in this recent commit (fixed as of
> the last round of minor releases):
> commit: cbc55da556bbcb649e059804009c38100ee98884
> committer: Michael Paquier <michael(at)paquier(dot)xyz>
> date: Mon, 9 Jul 2018 10:22:34 +0900
> Rework order of end-of-recovery actions to delay timeline history write
>
> And this thread:
> https://postgr.es/m/CABUevEz09XY2EevA2dLjPCY-C5UO4Hq=XxmXLmF6ipNFecbShQ@mail.gmail.com
>
> To give you a summary, once recovery finished and before recovery.conf
> was renamed, some on-disk actions happened, which could put the cluster
> in a weird state, perhaps similarly to what you saw.

How would this address OP's concern? You'd still not learn meaningfully
earlier that your attempted promotion failed (instead of learning of the
problem before you ever promote).

Greetings,

Andres Freund