How to setup an autodiscovery

Hello everybody,
I’m a computer engineering student.I’m doing a thesis on Industrial Ethernet. I needed a tool that allow me to do the following things and people suggested me LibreNMS:

1.Autodiscovery of the devices connect to a LAN(MAC address and IP address).
2.Draw a L2 topology map.
3. Bandwith usage for each link
4.Protocols that are present in each link

I installed it in a VM with Ubuntu Server 18.04. I’m wondering out to run an autodiscovery for my network,whenever I want.

Thanks in advance for your help,

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