NetDisco — Open Source Network Inventory with a Web UI
General Information
NetDisco is an open-source app that many admins keep in their toolbox for one reason: it shows where everything is plugged in. Instead of digging through spreadsheets or walking to wiring closets, NetDisco asks switches and routers directly and builds its own inventory. It’s not flashy, but it does the job — map devices, find hosts, and keep track of connections.
How It Works
The tool talks to switches and routers using SNMP and sometimes CLI. It pulls data like MAC-to-port mappings and ARP tables, then stores that in a database. From there, the web interface lets you search by IP, MAC, or hostname to see exactly which port a device is hanging off. In larger LANs, this saves hours when tracking down a problem machine or checking where a user is connected.
Functions
| Feature | What It’s For |
| Device discovery | Pulls data from switches and routers to build an inventory. |
| Host tracking | Shows which switch and port a host is connected to. |
| Search | Quick lookup by IP, MAC, or hostname. |
| Inventory | Keeps records of devices and connection history. |
| Topology hints | Shows relationships between devices. |
| Browser-based | Everything is done through a web UI, no client install. |
Installation Notes
Most admins run NetDisco on a Linux server. Setup involves PostgreSQL for the backend and Perl modules for the app. On Debian/Ubuntu it usually goes like this:
– Install packages: apt install build-essential libsnmp-dev postgresql.
– Create the database and user.
– Install NetDisco from CPAN or the official bundle.
– Edit netdisco.yml to set SNMP communities and DB details.
– Start the services, then open the UI at http://server:5000.
There’s also a Docker image that makes things easier if you don’t want to handle dependencies manually.
Everyday Use
Admins like NetDisco because it cuts down time when answering questions such as “Where is this device connected?”. During security incidents, plugging a MAC address into the search shows the exact switch and port instantly. It also helps with asset tracking — instead of updating Excel sheets, the system builds its own inventory from live network data.
Limitations
It only works well with managed devices that speak SNMP. If you have cheap unmanaged switches, they won’t show up properly. Also, NetDisco is about discovery and inventory, not monitoring performance or generating alerts. Most admins combine it with tools like Zabbix or Grafana for that side of things.
Comparison
| Tool | Platforms | Strengths | Best Use |
| NetDisco | Linux | Discovery + host location, searchable inventory | Enterprise/campus LANs |
| LanTopoLog | Windows | Visual topology maps, SNMP-based | Small/medium networks |
| NetCrunch Tools | Windows | Set of quick diagnostic utilities | Troubleshooting on desktops |