Application monitoring

Hi all:

We maintain a number of web-based applications that use postgres as the back
end. We recently had an unfortunate situation where the hosted server was
hacked and the client had some significant downtime. We proposed a custom
monitoring app, written in PHP, that would periodically monitor (for
example) the web server (Apache) and database (postgres) so that we¹d know
more quickly when something happened.

The client responded that surely this problem of monitoring a
database-backed web app was a known, solved problem, and wanted to know what
other people did to solve the problem.

So my question, hopefully not too off-topic: if you administer a
mission-critical postgres install that needs high availability, what do you
do for monitoring? Commercial, freeware or open source tool? Custom scripts?
Anything I haven¹t thought of?

-- sgl

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Steve Lane

Vice President
The Moyer Group
14 North Peoria St Suite 2H
Chicago, IL 60607

Voice: (312) 433-2421 Email: slane(at)moyergroup(dot)com
Fax: (312) 850-3930 Web: http://www.moyergroup.com
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