I'd come to the same conclusion Jeremy had about 9.5 being the first version with the 'always' option for archive_mode. Looking at pg_receivexlog, that might work, but with me being a total noob I'm wary of the various steps I'd have to take in going from:
Master -> streaming replication to -> SB1 -> pg_receivexlog to -> SB2
to:
New Master (Old SB1) -> streaming replication to -> SB2
And whether or not the conversion from pg_receivexlog to normal streaming replication would maintain data integrity. I need to skew this towards simplicity or I'll likely screw it up.
My current thought is to cut off master, promote SB1, set up WAL file shipping to SB2, start a pg_basebackup, make SB1 live, then run for a couple days with no backup as the pg_basebackup runs. Far from ideal but at least I have gone through most of this before.
From: Michael Paquier <michael.paquier@gmail.com>
Sent: Monday, November 13, 2017 6:01 PM
To: Jeremy Schneider
Cc: ericd81@hotmail.com; PostgreSQL General; Paul Jungwirth
Subject: Re: [GENERAL] archive_command not being executed
On Tue, Nov 14, 2017 at 8:56 AM, Jeremy Schneider
<schneider@ardentperf.com> wrote:
> From my reading of the docs and commit logs, standby databases
> couldn't archive their WALs until 9.5.
pg_receivexlog is available in 9.3. You could leverage your archives
with it easily, by for example connecting it to a standby you'd like
to get the archives from.
--
Michael