So far, we have largely executed the manual configuration of Zabbix by adding hosts, items, triggers, and other entities. With the exception of templates as discussed in Chapter 8, Simplifying Complex Configurations with Templates, we haven't looked at ways to accommodate larger and more dynamic environments. In this chapter, we will discover ways to automatically find out about resources such as network interfaces or filesystems on hosts by using low-level discovery, scanning a subnet using network discovery, and allowing hosts to register themselves using active agent auto-registration.

While learning about these methods, we will also explore related features, such as global regular expressions, and find out more details regarding the features we are already aware of—including context for user macros.

As Zabbix has several ways to manage automatic entity configuration and they all operate in a different manner, it is highly recommended never using the term auto-discovery when talking about Zabbix—nobody would know for sure which functionality is meant. Instead, it is always recommended specifying whether it's low-level discovery (LLD), network discovery, or active agent auto-registration.

We will cover the following topics in this chapter:

• LLD
• Creating custom LLD
• Global regular expressions
• Network discovery
• Active agent auto-registration