Arpio

(Linux + MacOS) Fast, minimal LAN discovery using ARP and mDNS. Single binary.

Features

• Active ARP discovery (Linux + macOS)
• Passive ARP listening
• mDNS hostname discovery
• Live watch mode
• JSON output
• Auto interface detection or manual override

Build

go build

ARP requires elevated privileges.

Usage

Active scan

sudo ./arpio scan

Passive scan (listen only)

sudo ./arpio scan --passive

JSON output

sudo ./arpio scan --json

Select interface

sudo ./arpio scan --iface en0

Disable mDNS

sudo ./arpio scan --mdns=false

Watch mode (live table)

sudo ./arpio watch
sudo ./arpio watch --iface en0 --interval 2s

Passive watch:

sudo ./arpio watch --passive

Notes

• Linux uses native ARP sockets
• macOS uses pcap for ARP capture and injection
• Results depend on network activity and privileges