PortFinder

Network switch port discovery tool. Captures CDP (Cisco Discovery Protocol) and LLDP (Link Layer Discovery Protocol) packets to identify what switch, port, and VLAN your device is connected to.

What it does

1. Select a network interface (or sniff all)
2. Choose protocol — CDP (Cisco) or LLDP (Aruba, HP, etc.)
3. Click Start and PortFinder captures the next discovery packet
4. Displays: Switch Name, Switch IP, Switchport, Native VLAN, Voice VLAN, MTU, Switch Model

Screenshots

• macOS

  ---

  

• Windows

  ---

  

• Linux

  ---

  

• CLI

  ---

  

At a glance

GUICLI

Cross-platform desktop app on macOS, Windows, and Linux. Native widgets per platform.

The same binary works headless. Use portfinder capture --interface en0 --protocol LLDP and pipe --json into your scripts.

Get started

• Install — .dmg, .deb, .rpm, .AppImage, .exe
• GUI usage
• CLI usage

Source

Source on GitHub: packetThrower/PortFinder