Telegraf is an agent that collects metrics from various input channels and writes them to output channels, supporting over 60 plugins for both inputs and outputs. It can be used to monitor system parameters such as CPU, memory, disk usage, and more on the InfluxDB server itself, with the system input plugin capturing these metrics and sending them to an output channel, in this case, InfluxDB. Telegraf's configuration file allows for customization of plugins and settings, including the interval at which data is collected, and can be generated using a command that includes the desired input and output filters. With Telegraf installed on the InfluxDB server, metrics are collected and written to the database, allowing for further analysis and visualization through tools like Chronograf or alerts through Kapacitor.