Monitoring Taxonomy

Chapter 7. traditional.free_open.monoliths.system

By far the most popular category, the tools in this chapter are what most people envision when they think of monitoring tools: a single-process daemon that collects availability data about servers.

Check_MK: Making Nagios Easier

Check_MK began life as an easier-to-use remote execution framework for Nagios (read: agent), but it is usable today as a stand-alone tool. It would be a straightforward agent were it not for the various complications inherent in integrating with a pre-existing Nagios system. These mostly include the typical configuration Nagios needs before it can accept check results for hosts and services.

To work around Nagios’ configuration complexities, Check_MK embeds a fully fledged service discovery system and Nagios configuration generator, enabling you to scan for new hosts and add them to your pre-existing Nagios configuration with a few command-line interface commands. Check_MK then follows up by adding a queriable state socket for the Nagios daemon, a replacement UI, and even a web-based Nagios configuration service, making it an extremely popular one-stop Nagios simplification system.

Push, Pull, Both, or Neither?

Depending on how you configure it, Check_MK can proxy active checks (pull) or it can operate passively (push). Even if you configure it for active checking, however, Check_MK is a far more efficient poller than Nagios core is, interacting once with each remote system it monitors per polling interval ...