Benjamin <benjamin (AT) netyantra (DOT) com> writes:
The only adequate "lock" for that sort of thing is to shut down the
postmaster on A. Anything less is simply not trustworthy.

There is support coming up in 8.0 for WAL archiving and point-in-time
recovery. With that, you could do the scp without any lock and then
fix up discrepancies by replaying the WAL archives for the interval that
the scp was running. Furthermore you could continue to ship WAL
segments to B to keep it up to date with A, without needing repeated
full scp's. See
http://developer.postgresql.org/docs...es/backup.html
for some preliminary documentation about this.

Slony looks like a pretty good alternative too, and it's available now.
But don't bother trying to roll your own replication setup. It's
unlikely that you can easily build a reliable one.

regards, tom lane

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Benjamin wrote:
If I understand you correctly, "Slony" will do exactly what you
want, without the need to lock any DB: http://www.slony.org
Slony 1.0 has been released recently, which was mentioned
prominently on PostgreSQL's homepage. It's a master-slave
replication system.

Hope that helps.

Best regards
Oliver

--
Oliver Fromme, secnetix GmbH & Co KG, Oettingenstr. 2, 80538 München
Any opinions expressed in this message may be personal to the author
and may not necessarily reflect the opinions of secnetix in any way.

"UNIX was not designed to stop you from doing stupid things,
because that would also stop you from doing clever things."
-- Doug Gwyn

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Oliver Fromme wrote:

Yea.. slony seems to be good. We just might HAVE to use that in the near
future.
But as of now, we r shutting down pgsql on A, while the duplication is
being done, as Tom suggested.


--

Benjamin Jacob.

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