What Lantern v1.6.7 does—and what it does not claim to do

Lantern is a local network monitor for Windows. You select IP addresses or hostnames to probe with ICMP; Lantern presents live state, latency, packet loss, availability, retained graphs, outage records, diagnostics, discovery, and application-health information in a local browser interface.

Lantern is offered free of charge. “Free” does not imply a particular open-source licence; no licensing terms beyond the project’s published distribution terms are asserted here.

The packaged application is for 64-bit, x64-compatible Windows. Its installer requires administrator privileges because it installs a Windows service. This site does not claim Linux, macOS, Windows on ARM, or a specific Windows-edition support matrix.

No Lantern cloud account or remote monitoring service is required. The web UI and database are local. Internet access is needed only when you choose to monitor or diagnose Internet targets, resolve external names, or obtain the application through a separately published download.

In an installed build, the database and logs use the machine-wide Lantern directory under Windows ProgramData. Settings displays the exact active paths, so use those values rather than assuming a drive letter or development path.

No application telemetry or analytics upload is implemented in v1.6.7. Lantern does send the ICMP, route, DNS, and scanner traffic required for targets and diagnostics you request; those checks are the product’s function, not telemetry.

Normal monitoring uses ICMP. A firewall or device may ignore ICMP while other services work. Confirm the exact target and test ICMP from the Lantern machine before treating Offline as proof that every service is unavailable.

The host has not met the Offline failure threshold, but at least three of its latest five successful latency samples exceed its threshold, or rolling loss is at least 20% in the current 60-second window. Recovery requires three consecutive healthy successful probes. Degraded events are separate from outages.

For an enabled target, it collects target reachability, route context, gateway reachability, DNS-server reachability and an optional direct DNS query, plus traceroute information. Results can be complete, partial, failed, or cancelled. They provide correlated evidence, not a guaranteed root cause.

v1.6.7 implements Gateway and DNS Server roles. There is no separate Internet role. To use an Internet reference point, add the endpoint as a normal monitored host and enable Advanced Diagnostics for it.

It accepts an IPv4 CIDR or start/end range of at most 1,024 addresses and reports devices that answer ARP on a directly connected subnet or ICMP. Hostname, MAC address, and manufacturer are best-effort and can be blank. A missing result does not prove an address is unused.

Yes. Raw, one-minute, one-hour, and finished diagnostic-run history have separate retention choices. Outages, degraded events, and monitoring errors are not governed by those selectors. Clear Monitoring History removes recovered outages and inactive degraded events; v1.6.7 has no Settings control for deleting monitoring-error records.

Clear All Data removes all samples and rollups, recovered outages, inactive degraded events, and finished diagnostic runs. It preserves hosts, groups, roles, settings, active incidents, queued/running runs, and monitoring errors. Optimize Database compacts and integrity-checks SQLite without intentionally deleting data. Neither is an undo or backup.

Open Settings and use the displayed Log file path. Lantern uses a rotating application log, and recent monitoring errors also appear in Application Health. Include a sanitized excerpt, the displayed version, target, and time when reporting a reproducible problem.

Lantern is a focused, single-machine local monitor. v1.6.7 does not provide a hosted control plane, distributed collectors, accounts, role-based access, or a public remote-management interface. Keep its loopback web listener local.

Use the reporting channel published with the release you installed. Include the version, Windows environment, reproduction steps, timestamps and targets, and a sanitized log excerpt. This site does not invent an issue-tracker URL or support email.