Cisco MAC OUI Resolver (GUI)

Offline bulk OUI lookup for Cisco show mac address-table output.

• Paste or load text
• Keeps VLAN + Interface with each MAC
• Optional Exclude Port-Channels (Po)*
• CSV export (Hostname | VLAN | Interface | Mac | Vendor)
• UI and CSV both sorted numerically by Interface
• Windows-friendly; can be built as a single .exe

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Run from source

py -m venv .venv
.\.venv\ScriptsActivate
pip install -r requirements.txt
py oui_lookup_gui.pyw

Build a Windows EXE

pip install pyinstaller
py -m PyInstaller --noconfirm --noconsole --onefile --name OUILookup oui_lookup_gui.pyw
# output: dist/OUILookup.exe

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Getting the vendor database (manuf)

Some networks (corp TLS inspection) block the app from downloading the Wireshark manuf file. If the app can’t pull it, use the standalone downloader and import the file:

1. Double-click the standalone downloader get_manuf.pyw.
   It saves a file named manuf in the same folder as the script.
2. In the GUI, click Import DB and select that manuf file.
3. The app will cache a copy at %USERPROFILE%\.oui_lookup\manuf for future runs.

If your network allows it, Update DB will try to download manuf directly. If it fails, use the standalone script above.

Where the DB lives (after import/update)

%USERPROFILE%\.oui_lookup\manuf

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Notes

• CPU rows are skipped automatically.
• Unknown OUIs show Unknown.
• Export default filename: <SourceDevice>-MAC-OUI.csv (e.g., 73-01-SW01-MAC-OUI.csv).
• The Import DB button lets you run fully offline.
• Auto-detects Source Device from pasted prompts like SW01# or SW01>.

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Troubleshooting (for builders)

If PowerShell blocks venv activation:

Set-ExecutionPolicy -Scope Process -ExecutionPolicy Bypass
.\.venv\Scripts\Activate.ps1

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License

MIT