Chapter 5. Principles of Operation

Table of Contents
Data Retrieval
Data Storage
Data Presentation

Cacti operation may be divided into three different tasks:

Figure 5-1. Principles of Operation

Data Retrieval

First task is to retrieve data. Cacti will do so using its Poller. The Poller is executed from the operating system's scheduler, e.g. crontab for Unix flavored OSes.

In current IT installations, you're dealing with lots of devices of different kind, e.g. servers, network equipment, appliances and the like. To retrieve data from remote targets/hosts, cacti will mainly use the Simple Network Management Protocol SNMP. Thus, all devices capable of using SNMP will be eligible to be monitored by cacti.

Later on, we demonstrate how to extend cacti's capabilities of retrieving data to scripts, script queries and more.