To generate graphs, Cacti needs to collect data. Cacti, by default, comes with some data queries and data input methods, which are enough for small and medium networks, but if you have a large network with 100+ computers, routers, and network devices, writing some data queries and input methods may save you time.
In this chapter, we will learn:
How to create data input method.
How to create data query.
SNMP query XML syntax.
Script query XML syntax.
Creating graph for single SNMP OID.
In Cacti, data is collected by two methods:
1. The data input method.
2. The data query method.
In Chapter 4, we learned about the data input method. Here, we'll learn to create data input methods. Data input methods are the basic system that Cacti uses to collect data for generating graphs.
In the above figure, we can see the list of input methods that come with Cacti. For most small networks, you don't need to add or create a custom data input method. For larger networks...