arping

Arping as a command-line tool has to be installed first as it doesn’t come native on your Chrome OS system. The tool is similar to the ‘ping’ utility popular for testing networks as well as aiding system discoverability. The primary difference between the ‘ping’ and ‘arp’ commands comes down to the protocol they’re powered with. The former typically uses the Internet Control Message Protocol (ICMP), while arping is powered by the Address Resolution Protocol (ARP).

Using arp-scan in ChromeOS requires root privileges:

$ sudo su

The above command will switch you to “root” in the Linux terminal. Be careful when in root.

Switch back to the default user using the command below:

$ su username

Target hosts must be specified on the command line unless the –file option is given, in which case the targets are read from the specified file instead, or the –localnet option is used, in which case the targets are generated from the network interface IP ad‐
dress and netmask.

You will need to be root, or arp-scan must be SUID root, in order to run arp-scan, because the functions that it uses to read and write packets require root privilege.

The target hosts can be specified as IP addresses or hostnames. You can also specify the target as IPnetwork/bits (e.g. 192.168.1.0/24) to specify all hosts in the given
Manual page arp-scan(1) line 1 (press h for help or q to quit)

Install using:

$ sudo apt install arping

$ sudo apt install arp-scan

You can use it as below to find all alive hosts on a network:

$ sudo arp-scan –interface=enp2s0 –localnet