Horton

Re: Standalone synchronous master

Stephen Frost <sfrost@snowman.net>

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From: Stephen Frost <sfrost@snowman.net>
To: Andres Freund <andres@2ndquadrant.com>
Cc: "Joshua D. Drake" <jd@commandprompt.com>, Tom Lane <tgl@sss.pgh.pa.us>, Kevin Grittner <kgrittn@ymail.com>, Bruce Momjian <bruce@momjian.us>, Heikki Linnakangas <hlinnakangas@vmware.com>, Simon Riggs <simon@2ndQuadrant.com>, Rajeev rastogi <rajeev.rastogi@huawei.com>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2014-01-08T23:05:47Z
Lists: pgsql-hackers 
* Andres Freund (andres@2ndquadrant.com) wrote:
> On 2014-01-08 17:56:37 -0500, Stephen Frost wrote:
> > * Andres Freund (andres@2ndquadrant.com) wrote:
> > > That's why you should configure a second standby as another (candidate)
> > > synchronous replica, also listed in synchronous_standby_names.
> > 
> > Perhaps we should stress in the docs that this is, in fact, the *only*
> > reasonable mode in which to run with sync rep on?  Where there are
> > multiple replicas, because otherwise Drake is correct that you'll just
> > end up having both nodes go offline if the slave fails.
> 
> Which, as it happens, is actually documented.

I'm aware, my point was simply that we should state, up-front in
25.2.7.3 *and* where we document synchronous_standby_names, that it
requires at least three servers to be involved to be a workable
solution.

Perhaps we should even log a warning if only one value is found in
synchronous_standby_names...

	Thanks,

		Stephen