you can do this with nagios too, if you are allowed to
run a remote agent like nrpe on the servers.
for example check_logfiles
is really great plugin,
you can use it together with nrpe and nagios. It is quite powerful.
Everything else that is not covered by already existing plugins can be scripted and easily integrated with nrpe.
Anotherway is to export this data via snmp and use cacti to store and display it.