PostgreSQL server architecture

We run a small in-house data centre for our various
operations.  Currently, we are moving applications from
dedicated boxes to kvm based CentOS-6.1 virtual machines
on a single CentOS-6.1 host.  At issue is the question on
how to handle the PostgreSQL instances that we currently
have running on different machines.

As we see it presently we have the option of having one VM
host a centralized PostgreSQL server with multiple
databases or continue with each application specific VM
running its own copy of PostgreSQL with just the dedicated
application database.

Since whatever we chose we are likely to be using five
years from now I am soliciting informed option over which
option is considered a better choice for the long term.

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James B. Byrne                mailto:ByrneJB@Harte-Lyne.ca
Harte & Lyne Limited          http://www.harte-lyne.ca
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Hamilton, Ontario             fax: +1 905 561 0757
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