Trying to choose a network monitoring service; the number of choices is bewildering. Nagios is probably the most popular open source solution, but it seems massively overengineered and complex for my simple needs (of monitoring a handful of services on two hosts). Zabbix looks decent but also looks like overkill. I am thinking of writing a really simple script, using RRDTool for storage (nice example of how to do that here). Could put a simple Sinatra-based front-end on it.