Re: How can I avoid PGPool as a single point of failure?

Hello...

snewman18@gmail.com wrote:
>
> I'm interested in using PGPool to do the load balancing, and it was
> suggested that I put one server running PGPool in front of two
> database servers. This only seems to move my risk to the PGPool
> machine.
>
You could use linux hearbeat to allow one Pgpool server to "watch after"
another (and take over in the case of a failure), or you could try to do
something with CARP or some other related balancing scheme.  In the CARP
case you would have a single master that would respond to network
requests, and another slave (running pgpool) that would sit idle until
it needed to leap into action to "save the day".
> Is it possible to point two servers running PGPool at the same two
> database servers? If so, I seem to recall reading about being able to
> use some kind of virtual IP address to split the traffic to both.
CARP...I've never tried to use it for such a thing (I've used it for
firewall redundancy in the past..which is what I think it was designed
for), but I'm fairly certain you could do so without too much trouble.

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Chander Ganesan
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