The Open source market is getting overcrowded with different Network monitoring solutions, and not without reason, monitoring your infrastructure become more important each day, you have to know what's going on for your boss, your customers and for yourself. Nagios started the evolution, but today OpenNMS, Zabix, Zenoss, Groundworks, Hyperic and different others are showing up in the market. Do you want lightweight, or feature full, how far do you want to go with your monitoring, just on os level, or do you want to dig into your applications, do you want to know how many query per seconds your MySQL database is serving, or do you want to know about the internal state of your JBoss, or be triggered if the OOM killer will start working soon. This presentation will guide the audience trough the different alternatives, based on our experiences in the field. We will be looking both at alerting and trending and how easy or difficult it is to deploy such an environment.