Re: Mirroring databases in v8

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Glen Eustace <geustace(at)godzone(dot)net(dot)nz>
Cc: Shridhar Daithankar <shridhar(at)frodo(dot)hserus(dot)net>, pgsql-general(at)postgresql(dot)org
Subject: Re: Mirroring databases in v8
Date: 2004-10-06 14:06:16
Message-ID: 25460.1097071576@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

Glen Eustace <geustace(at)godzone(dot)net(dot)nz> writes:
> Having read this, it would seem I might be jumping the gun a bit. The
> method given could be used to copy a running database to another system
> but I'm not sure how it would work if the mirrored database is required
> to be online at the same time.

It wouldn't. You can have a "hot spare" database via log shipping, but
there is zero chance of allowing the backup to run any independent
transactions. (If it did, its xact counter and pg_clog would get out of
sync with the master, causing all subsequently copied data to be
invalid. AFAICS, even read-only transactions would be problematic.)

Not sure if you are familiar with the Slony project, but that is
probably your best bet for data propagation to a live slave at present.

regards, tom lane

In response to

Responses

Browse pgsql-general by date

  From Date Subject
Next Message pginfo 2004-10-06 14:17:24 Re: lower/upper support and cyrillic
Previous Message Justin Wyer 2004-10-06 13:30:49 two digit years in inserts