scanlan 0.1.0

Find devices on your LAN without the headache.

scanlan

Find devices on your LAN without losing your mind.

  scanlan  → 192.168.1.0/24

  IP ADDRESS       HOSTNAME              MAC ADDRESS        VENDOR
  ──────────────────────────────────────────────────────────────────────────
  192.168.1.1      router.local          A4:77:33:12:AB:CD  Google
  192.168.1.42     —                     B8:27:EB:4F:12:99  Raspberry Pi Foundation
  192.168.1.55     macbook-pro.local     AC:BC:32:88:11:22  Apple
  192.168.1.101    android-phone.local   38:AA:3C:77:44:55  Samsung

  4 devices found on 192.168.1.0/24

nmap is great. But when you just want to find your new Pi on the network, it's overkill. scanlan does the one thing you actually need: scan your subnet, show you what's there, and tell you what it is.

Zero dependencies. Pure stdlib. Works on Linux, macOS, and Windows.

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Install

pip install scanlan

Note: Scanning requires sending ICMP pings and reading the ARP table. On Linux/macOS you may need to run with sudo (or grant ping capabilities).

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Usage

scanlan [options]

Just run it

scanlan

Auto-detects your subnet and scans it. Raspberry Pi rows are highlighted in green.

Check open ports too

scanlan -p

Checks ports: 22 (ssh), 80 (http), 443 (https), 8080, 8443, 3389 (rdp), 5900 (vnc), 554 (rtsp), 1883 (mqtt), 8883

Wait for a device to appear

scanlan -w

Re-scans every 5 seconds and prints new devices as they show up. Perfect for waiting on a Pi to boot.

scanlan -w --interval 10   # check every 10 seconds instead

Scan a specific subnet

scanlan -s 10.0.0.0/24

JSON output (for scripts)

scanlan --json
scanlan --json | jq '.[] | select(.vendor | contains("Raspberry Pi"))'

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All options

  -s, --subnet CIDR     Subnet to scan (auto-detected if not given)
  -p, --ports           Check common ports on each device
  -w, --watch           Watch for new devices continuously
  --interval SECONDS    Seconds between watch-mode scans (default: 5)
  --json                Output as JSON
  --workers N           Parallel workers (default: 64)
  --version             Show version

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How it works

1. Pings every host in the subnet in parallel (default 64 workers)
2. Reads the ARP table for MAC addresses of responding hosts
3. Looks up the MAC OUI against a bundled vendor table (no internet needed)
4. Reverse DNS each IP for a hostname
5. Optionally checks ports with TCP connect

The bundled OUI table covers the most common home/office vendors (Raspberry Pi, Apple, Google, Amazon, TP-Link, ASUS, Samsung, Ubiquiti, etc.).

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Permissions

Platform	Required
Linux	sudo or CAP_NET_RAW for ping
macOS	sudo or group admin
Windows	Run as Administrator

Quick fix on Linux (no sudo every time):

sudo setcap cap_net_raw+ep $(which python3)

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License

MIT