I'm looking for a cheap (and quick to install) server monitoring solution.
What I'm interested in is to track the load and especially the disk usage as I'm sick
of logging in to my couple of webservers every day just to make sure the disk doesn't run full
and crashes my web server. Ideally I can setup an alert so I get notified via eMail if a certain value of disk usage / load is reached.
I tried phpsysinfo recently to troubleshoot a problem I (or, more precisely, my host,) was having and was delighted with its power and flexibility. It has a nice web interface, there's a Yahoo widget that supports it, it has an xml api, and the price is right ($0).