check_postgres.pl - a Postgres monitoring script for Nagios, MRTG,
Cacti, and others

check_postgres.pl is a Perl script that runs many different tests
against one or more Postgres databases. It uses the psql program to
gather the information, and outputs the results in one of three
formats: Nagios, MRTG, or simple.

WWW: https://bucardo.org/check_postgres/