Message-ID: <3DC2C771.7030106@clearmetrix.com>
Date: Fri, 01 Nov 2002 13:26:57 -0500
From: "Charles H. Woloszynski" <chw@clearmetrix.com>
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To: pgsql-sql@postgresql.org
Subject: HA PostgreSQL
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I am trying to develop a plan for a high-availability (HA) 
implementation of a database using PostgreSQL.  One wrinkle; the data we 
receive is performance data, and occassional loss of some measurements 
is Ok for us.  [I know, this is not in the main stream of database users 
:-)].

I have looked ar rserv and pg-replicator, and they seem to be targeted 
at replication without specific HA support.  Replication is great for 
lots of things; but I need HA more than ACID replication.  

I have seen a proposed solution that uses *rsync* on the database files 
between machines and linux-ha to roll over the network access to the 
available machine.  My question is pretty simple; can something as 
*simple* as rsync make a full copy of the database consistently between 
the machines?  That seems just too easy.  

If I replace the process with something that uses pg_dump and rsync that 
file (ok, now that seems more likely to generate a consistent database 
image) that and restore that into the slave, does this work?  Obviously, 
this approach is kinda a hammer approach; the poor active server will be 
dumping till the cows come home.

Any and all feedback and comments are greatly appreciated.  And, as 
always, thanks in advance,

Charlie

-- 


Charles H. Woloszynski

ClearMetrix, Inc.
115 Research Drive
Bethlehem, PA 18015

tel: 610-419-2210 x400
fax: 240-371-3256
web: www.clearmetrix.com