karlbaker / network-port-finder

This repo is a bundle pack on creating your own LLDP Discovery device. Useful for Network Engineers/Technicians.

Network Port Finder

Overview

The purpose of this script and associated to files is to create a small portable network device to identify the remote network device and it's associated port. This is done by leveraging the switch's Link Layer Discovery Protocol (LLDP) to provide that information.

The Why

There are plenty of professional tools that can provide this type of service, but they tend to be expensive and in limited quantity within an organization. This provides a quick solution when you're in a pinch trying to trace down mislabeled or unlabeled ports in rooms or patch panels.

Build of Materials (BoM)

• (1) Raspberry Pi Zero
• (1) 32GB microSD
• (1) Pisugar2
• (1) Waveshare 2.23 inch OLED Display HAT
• (1) Waveshare Ethernet/USB HUB HAT Expansion Board
• (1) 3D Printed case (See STL folder)
• (4) M2 4mm x 3.5mm Female Thread Knurled Nut - This is the set I'm using
• (4) M2x10 Screw - This is the set I'm using

Software Requirements / Tested Baseline

Note: Newer version of the listed software may work fine, but have not been tested. OS

• Raspbian GNU/Linux 11 (bullseye)"

Packages

• lldpd v1.0.11
• bmc2835 v1.71
• Python v3.9.2
• PiSugar Power Manager

OS File Structure

Copy the lib and network-port-finder directories to the root of your filesystem.

├── /network-port-finder/
│   ├── network-port-finder.py
│   ├── 04B_08__.TTF
│   ├── lcdlib/
│   │   ├── config.py
│   │   ├── SSD1305.py
│   │   ├── __pycache__/
│   │   │   ├── config.cpython-39.pyc
│   │   │   ├── SSD1305.cpython-39.pyc
├── /lib/
│   ├── systemd/
│   │   ├── system/
│   │   │   ├── network-port-finder.service

Installing the service

You can either run the setup.sh installation script or run through the manual setup that is outlined under the Manual Installation section on this README file.

To run through the installation script perform a git clone of this repo, navigate into the main directory then run sudo ./setup to kick off the installation.

• Note: The PiSugar Power Manager is still a manual process, run through the prompts and reboot your Pi once complete. It is important that a reboot occurs to get SPI working.

Manual Installation

There are a few packages that will need to be installed before starting the service.

Link Layer Discovery Protocol (LLDP) agent daemon

This daemon will pull the LLDP information from your infrastructure's network device. Use the following commands to install, start and enable the daemon at startup.

• sudo apt-get install -y lldpd

PiSugar Power Manager

This script will load the PiSugar Power Manager that will provide a continuous status of the PiSugar's battery life. Use the following command to install and start the power manager.

• curl http://cdn.pisugar.com/release/pisugar-power-manager.sh | sudo bash

Installation Steps - You'll be prompted with several steps to setup the Power Manager application.

• Select the appropriate PiSugar 2 model (mine is the PiSugar 2-LED Version)
• Enter in the HTTP authentication username (not needed for our purpose but its a part of the installation).
• Enter in the HTTP authentication password
• Press [Enter] at the Configuring pisugar-server prompt.
• Select the appropriate PiSugar 2 model at the Configuring pisugar-poweroff prompt.
• PiSugar Power Manager installation will be complete at this point.

OLED Display Setup

Run the following commands to setup the OLED display:

Enable SPI Interface

• sudo raspi-config
• Choose Interfacing Options -> SPI -> Select <Yes> to enable
• sudo reboot

Install BCM2835 Library

• wget http://www.airspayce.com/mikem/bcm2835/bcm2835-1.71.tar.gz
• tar zxvf bcm2835-1.71.tar.gz
• cd bcm2835-1.71/
• sudo ./configure && sudo make && sudo make check && sudo make install

Start Network Port Finder Service

The daemon would need to be reloaded using sudo systemctl daemon-reload command.

Use the following commands to start and enable the service at start up.

• sudo systemctl start network-port-finder.service
• sudo systemctl enable network-port-finder.service

LCD Display

When the daemon is started the LCD screen will display the port and battery status.

There will be (3) different status types:

1. ETH0 NOT CONNECTED - This indicates there is no network connection to the finder.
2. NO LLDP INFORMATION AVAILABLE - This indicates the finder's network port has a connection, but no LLDP information is being reported. This status usually occurs when finder is initializing the connection or the remote device has LLDP turned off or doesn't support it.
3. LLDP Information w/ data - This indicates the finder did pull the LLDP information from the remote device and will display remote device's MGMT IP, Hostname, and the connected port.

Note: The text will scroll to the left if the LLDP information is too long for the screen (<=25 characters).

Network Port Finder Case - STL 3D Print Files

The design is fairly rudimentary. If I was to remake the case I would try to keep it with in the 1RU space (1.75") and shrink down the thickness of the case.

• Lid: The (4) M2x10 Screw will be used to secure the lid to the base. Be careful: Tightening the screw too much will cause the nut to come out of the base.
• Base: The (4) M2 4mm x 3.5mm Female Thread Knurled Nut will be pushed into the cavities of the base. I used a heat source on the nut for the initial insertion then used a clamp to make the nut flush to the base.
• Slider: Use (1) M2x10 Screw to combine the two parts together. Insert 'Part B' into the inside and Part A will line up with Part B hole on the outside with the screw combining the two pieces.

Lid

Base

Slider Switch

Part A

Part B