LanTopoLog — Mapping and Watching LAN Topology
General Information
LanTopoLog is a Windows tool aimed at one thing: showing how the LAN is actually wired. Instead of keeping diagrams in Visio and guessing which switch port goes where, the program asks the switches directly (via SNMP) and draws the map automatically. For admins, that means less manual work and fewer surprises when tracing cables or explaining layout to colleagues.
How It Works
LanTopoLog polls managed switches, collects MAC and port data, and builds a diagram where devices and their links are visible. If a host disappears or a port goes down, the map updates. It’s not just a picture — the nodes on the screen reflect live status. Besides discovery, the program can watch bandwidth counters and basic device health through SNMP. Alerts fire when something important changes, for example, a trunk link drops or a device stops answering.
Main Functions
| Feature | Description |
| Auto discovery | SNMP queries build a topology map without manual drawing. |
| Device checks | Monitors uptime, port status, traffic counters. |
| Alerts | Sends notifications when devices or links fail. |
| Logs and reports | Keeps history, exportable for audits or troubleshooting. |
| Interactive map | Diagram updates in real time with device states. |
| Basic control | Some remote management actions available. |
Installation Guide
– Download the installer from the official website.
– Run setup with admin rights and follow the wizard.
– Start the program and enter SNMP community strings for switches.
– Launch discovery to let the tool build the map.
– Rearrange devices on the diagram if needed and save.
– Configure alert settings (pop-up, sound, email).
Everyday Use
In practice, LanTopoLog shines in small or mid-size LANs. It’s often used to replace static diagrams with something dynamic — handy when you need to know exactly which switch a workstation is connected to. During outages, the map helps narrow down the fault: one look at the diagram and it’s clear which link failed. For audits or documentation, the saved maps are much more accurate than hand-drawn diagrams.
Limitations
The tool relies on SNMP, so unmanaged or cheap switches won’t show up properly. It doesn’t scale well into large networks with thousands of nodes, and it has no deep integrations with other monitoring systems. For broader monitoring across servers and WAN links, admins usually combine it with tools like Zabbix or PRTG.
Comparison
| Tool | Platforms | Strengths | Typical Use |
| LanTopoLog | Windows | Auto topology maps, SNMP monitoring | Small to mid-size LANs, topology documentation |
| LANState | Windows | Visual maps + remote actions | Medium LANs needing both visibility and control |
| PRTG | Windows | Wide monitoring coverage, scalable | Enterprises with diverse infrastructures |