Comment by mmh0000

There's a famous quote:

  Those who cannot remember nmap are condemned to remake it poorly

Rootless nmap scan of a /24 in under 10 seconds:

  nmap -T5 -sn -PR --script broadcast-dns-service-discovery,broadcast-upnp-info 10.0.0.0/24
  …SNIP…
  Nmap done: 256 IP addresses (30 hosts up) scanned in 9.99 seconds

https://nmap.org/book/toc.html