PostgreSQL failover/cluster vs Microsoft SQL Server 2000

Hi All,

We are running a Microsoft SQL Server 2000 in cluster configuration
serving data to a farm of IIS Web Servers using Perl applications with
PerlEx.

We are seriously evaluating the opportunity to migrate to a Linux
environment with Apache web server, Perl applications using MOD_PERL
and PostegreSQL as the database.

A key factor is the ability to run PostgreSQL in High
Availability/Cluster configuration. How good is PostgreSQL on this?
Should I need a Linux cluster product? Which would be the most
appropriate?

I am also thinking of using a Network Attached Storage directly
connected to the database servers using Gigabit ethernet. Any problem
in running PostgreSQL on NFS?

Please reply directly to myself and I will then post a summary in the
newsgroup.

Many thanks in advance,

Osvaldo