X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id 08D669DCC8F for ; Tue, 7 Mar 2006 15:20:55 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 08457-10 for ; Tue, 7 Mar 2006 15:20:55 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey- Received: from mir3-fs.mir3.com (mail.mir3.com [65.208.188.100]) by postgresql.org (Postfix) with ESMTP id 9A3609DCC8E for ; Tue, 7 Mar 2006 15:20:52 -0400 (AST) Received: mir3-fs.mir3.com 172.16.1.11 from 172.16.2.68 172.16.2.68 via HTTP with MS-WebStorage 6.0.6249 Received: from archimedes.mirlogic.com by mir3-fs.mir3.com; 07 Mar 2006 11:20:50 -0800 Subject: Re: Postgres and Ingres R3 / SAN From: Mark Lewis To: "Jim C. Nasby" Cc: Jeremy Haile , pgsql-performance@postgresql.org In-Reply-To: <20060307190019.GX82989@pervasive.com> References: <20060306131355.A1227@ganymede.hub.org> <1141675112.28202.255960101@webmail.messagingengine.com> <20060307190019.GX82989@pervasive.com> Content-Type: text/plain Content-Transfer-Encoding: 7bit Organization: MIR3, Inc. Date: Tue, 07 Mar 2006 11:20:50 -0800 Message-Id: <1141759250.4237.7.camel@archimedes> Mime-Version: 1.0 X-Mailer: Evolution 2.0.2 (2.0.2-22) X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0.139 required=5 tests=[AWL=0.138, UNPARSEABLE_RELAY=0.001] X-Spam-Score: 0.139 X-Spam-Level: X-Archive-Number: 200603/73 X-Sequence-Number: 17510 On Tue, 2006-03-07 at 13:00 -0600, Jim C. Nasby wrote: ... > PostgreSQL on a SAN won't buy you what I think you think it will. It's > essentially impossible to safely run two PostgreSQL installs off the > same data files without destroying your data. What a SAN can buy you is > disk-level replication, but I've no experience with that. It is possible to run two instances against the same SAN using tools such as RedHat's Cluster Suite. We use that in-house as a cheap alternative for Oracle clustering, although we're not using it for our PostgreSQL servers yet. It's not for load balancing, just active/passive fault tolerance. -- Mark Lewis