Day one of a new IT contract. 200-person office.
I asked for the asset register.
There wasn't one.
Nobody could tell me how many devices were on the network, what they were, or who owned them. The IT manager had left six months earlier. His replacement was still finding their feet. This is more common than it should be.
I built a scanner. It sweeps the subnet, checks open ports to fingerprint device types, and produces a full register. No agents. No software installs. Just the network.
What it found on 192.168.1.0/24:
→ 24 active devices mapped in 30 seconds
→ Domain controllers, file server, Exchange, NAS, hypervisor, VoIP gateway — all undocumented
→ One Windows XP machine. Still live. Unpatched. No antivirus. Nobody knew it was there.
→ One completely unknown device — not in Active Directory, not documented anywhere
→ CCTV NVR with default admin credentials almost certainly still set
→ Printer web interface with no authentication
→ 5 risk flags raised for immediate action
The Windows XP machine was the one that stopped the room.
It had been sat there for years. Everyone assumed someone else was responsible for it. The previous IT manager had probably known about it and deprioritised it. Then he left.
That asset register — produced in 30 seconds — became the baseline for the entire site's IT documentation.
Built in Python. Runs on any subnet. The 30 seconds it takes has saved hours of guesswork on every contract since.
Interested in this project?
I'm always happy to talk through how it was built, the problems it solves, or how something similar could work for you.