Subject: Re: Backup solution over unreliable network
To: Stephen Frost <sfrost@snowman.net>,
 Achilleas Mantzios <achill@matrix.gatewaynet.com>
Cc: pgsql-admin@lists.postgresql.org
References: <fb7e7296-c60e-c2cc-93d5-9c2451e9a2a5@matrix.gatewaynet.com>
 <20181130120613.GW3415@tamriel.snowman.net>
 <6834c573-2a52-dd63-0264-5fc7258e7857@matrix.gatewaynet.com>
 <20181130152931.GY3415@tamriel.snowman.net>
From: David Steele <david@pgmasters.net>
Message-ID: <f185987a-6a38-055e-d4e7-fe53db824096@pgmasters.net>
Date: Fri, 30 Nov 2018 11:41:54 -0500
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On 11/30/18 10:29 AM, Stephen Frost wrote:
> * Achilleas Mantzios (achill@matrix.gatewaynet.com) wrote:
>> On 30/11/18 2:06 μ.μ., Stephen Frost wrote:
>>>> - I have only read the best reviews about PgBackRest, can PgBackRest address those issues?
>>> Glad to hear you've read good reviews about pgbackrest.  As for

<...>

> We've also considered supporting archive-mode=always and being able to
> have the standby also push WAL and while we may support that in the
> future, I'd say it's farther down on the list than multi-repo support.
> As I recall, David Steele also had some specific technical concerns
> around how to handle two systems pushing into the same WAL archive.
> Having archive-mode=always be allowed if it's going to an independent
> repo is an interesting thought though and might be simpler to do.

The issue here is ensuring that only one system is writing to the 
repository at a time.  This is easy enough if there is a dedicated 
repo-host but is much harder if the repo is on something like S3 or NFS.

Using independent repos might work, but we'd need a way to ensure the 
configuration doesn't get broken.

Regards,
-- 
-David
david@pgmasters.net