detection device connected over ethernet

[Abderrahmane]

Hi Everyone,

I would like to know how do i detect device connected over ethernet by OS Raspbian, I am using Raspberry Pi 3 model B+

[epoch1970]

Detect when/why?
If you're looking for a network scan tool, check out nmap.
Don't scan a network that is not yours or do so very slowly. Admins don't like it.

[Andyroo]

If you know the MAC address of the device then you can use arping to check if it’s connected.

Saves scanning the whole network if you have no idea where it is.