What are the two modes for the Zabbix agent?

The Zabbix agent operates in two primary modes: active and passive.

In passive mode, the agent listens for requests from the Zabbix server. The server initiates the communication and polls the agent for the required data. This mode is useful for scenarios where the server can routinely collect data without needing constant agent activity, making it simple to deploy in environments where the server can access all agents directly.

Active mode, on the other hand, allows the agent to initiate the communication itself. The agent actively sends data to the Zabbix server based on a predefined configuration. This mode is beneficial in environments with dynamic IP addresses or firewalls since agents can push data out without waiting for the server to request it. Active mode also reduces the server's load because it does not have to constantly poll the agents.

Understanding these two modes helps in optimizing data collection, managing resources efficiently, and configuring Zabbix agents according to the network setup and administrative preferences.