At what levels can macros be defined in Zabbix, and what is their precedence order?

Macros in Zabbix are defined at different levels, and understanding their precedence is essential for effective monitoring setup. The correct approach to this involves recognizing that macros can be defined at the global level, the template level, and the host level, each with specific characteristics and scopes.

When a macro is defined at multiple levels, the order of precedence determines which macro value will be utilized when referenced. The correct precedence order is that host-level macros take priority over template-level macros, which in turn take precedence over global macros. This means if a host has a specific value set for a macro, that value will be used instead of any corresponding value defined at the template or global levels.

This hierarchy allows for flexible customization of monitoring configurations. For instance, if a template is used for multiple hosts, the global macro can provide a default value, while individual hosts can override this with their specific macro value as necessary, ensuring that monitoring remains relevant and tailored to the particular needs of each host.

Understanding this precedence is crucial for Zabbix users to avoid conflicts and ensure that the correct values are applied in their monitoring configurations.