After struggling with none of the other tools listed here quite fitting their needs, internet application and support company OmniTI built a solution optimized for their needs named Reconnoiter and released the results to the world recently.
Compared to Nagios, it's less complicated to set up, it is optimized to use less resources, and has built-in trending capabilities. It uses a standard PostgreSQL database to store its data, which provides some synergy if you're already using it for other purposes, and instead use the RRDtool approach where storage is reused aggressively, Reconnoiter considers using large amounts of disk space for logging historical data at a fine time scale a feature rather than a problem.
As shown in the ...
