[Pgpool-general] Pgpool-general Digest, Vol 59, Issue 3

[Agustin Almonte Ferrada]

Hi Avi,

We are using pgpool in a similar configuration. One balancer, four  
servers with his own pgpool and two backends.

Each pgpool is configured to replicated inserts and updates, and  
select queries are balanced between backends. This configuration is  
working without problems after some patches applied to the latest  
version of pgpool.

Hope this helps you.

Cheers
Agustín Almonte F.





El 03-10-2009, a las 8:00, pgpool-general-request at pgfoundry.org  
escribió:

> ----------------------------------------------------------------------
>
> Message: 1
> Date: Fri, 2 Oct 2009 14:55:28 -0500
> From: Avi Blackmore <support at satshot.com>
> Subject: [Pgpool-general] Redundant pgpool-II nodes?
> To: pgpool-general at pgfoundry.org
> Message-ID: <AFBBB63B-1F0A-4827-A2EA-3559685CA023 at satshot.com>
> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
>
> Hi,
>
> 	Our current server setup is a main server with web, application and
> database (PostgreSQL 8.3) servers and a RAID unit for mass storage.
> I'm looking to set up a redundant server and RAID unit, colocated at a
> nearby location, to make use of load-balancing and do transparent
> failover in case of problems.  Obviously, we need database replication
> to do this.
>
> 	PGPool-II looks like a good solution, since it handles DDL
> replication, is synchronous, and can do multimaster replication.
> Also, it load-balances, which is nice.  But, my concern is that having
> one PGPool server process, running on just one machine,  just makes
> that server process (and its machine) a single point of failure.  This
> defeats the purpose, since my entire goal is to enable 100%
> transparent failover, with no downtime in the case of a single server
> (or RAID unit) failing.
>
> 	Ideally, what I would like to do is have TWO PGPool processes, one
> per machine, and have them talk to both backends, and synchronize with
> each other so as to avoid conflicts.  But I'm not certain this is
> possible.  Can two instances of PGPool communicate with each other in
> the way I'm describing?  If not, is there another way to use PGPool to
> achieve what I'm trying to do?
> --
> Avi Blackmore
> Head Programmer/System Administrator
> Agri ImaGIS Technologies, Inc.
>