In this chapter, we covered a large number of components. We started our discussion from the most used and even very critical network service: DNS. Going ahead on the same way, we discussed DNSSEC; then, we moved on to Apache, the most used and effective reverse proxy; walked through NTP; and closed the chapter with Squid, the most installed and used proxy service. For all the systems and services analyzed, you're now able to acquire the most critical metrics, and you know how to create effective triggers.

Triggers here are covering the most critical role and hence your experience within your network is the truly added value. You, with the knowledge acquired from this chapter and your environment experience, will be the key to creating effective and proactive triggers. This chapter has covered all the critical services you can find in a network, and now you can easily provide a heavy added value, creating proactive checks and installing an effective, tailor-made monitoring solution...