No WiFi needed
There’s no smart plug to drop off the network. The relay is wired to the firewall, so the site needs no WiFi at all.
Vigil · os-vigil
The OPNsense modem watchdog.
Vigil runs on your firewall and drives a USB relay. When the ISP stops handing out a DHCP lease, it recovers the connection — trying the safe fix first, cutting power only when nothing else works.
Use case
For the remote site with no WiFi and no spare port.
Plenty of modem-recovery gadgets need a WiFi network or an Ethernet port you don’t have. Vigil needs neither — the relay is driven over USB straight from the firewall.
No Ethernet port used
It plugs into a USB port on the firewall — no sacrifice of a switch port you need for something else.
USB, straight from the router
The firewall flips the relay over USB. One free USB port is the whole footprint.
What it does
Recovery without a truck roll.
Power is the last resort
Vigil tries a DHCP renewal first, which often restores the link with no outage at all.
Hung modem, or ISP outage?
If the WAN gateway still answers, the fault is upstream and a power cycle cannot help — so Vigil does not cycle.
A rolling 24-hour budget
A cap on how often it can switch means a fault it cannot fix never becomes a modem rebooting all night.
Fails with the modem on
If the relay loses power or is unplugged, the contact closes and the modem keeps running. Only a deliberate cycle cuts power, and only for about 30 seconds.
How it’s wired
In line, between the modem and its power supply.
The relay sits on the modem’s DC line through COM and NC — a normally-closed contact — so the modem keeps power even if the relay fails. The NO terminal is left unused.
How it’s licensed
The licence is inventory, not enforcement.
Vigil checks in daily and keeps itself updated. A lapsed licence costs you updates and shows a status line in the GUI — and nothing else.
That is deliberate. A watchdog that stopped working when its licence lapsed would fail exactly when a site is offline. The relay never cares about licence state; a test fails the build if anyone tries to wire it in.
What a licence actually gives you
- Automatic package updates
- Per-device check-in and fleet reporting
- Support for the sites you run
The watchdog itself keeps working, licensed or not.
Requirements
What you need to run it.
An OPNsense firewall
The os-vigil package installs on OPNsense, the only supported platform today. Windows, Linux, Ubiquiti EdgeOS and OpenWRT are in progress.
A USB relay
A commodity USB relay wired COM + NC between the modem and its power — so the modem stays powered even if the relay fails.
A modem worth recovering
Any modem on a DHCP uplink. If the WAN gateway still answers, Vigil leaves it alone — the fault is upstream.
In the OPNsense UI
See it where you manage your firewall.
Vigil
Buy the relay, licence for a year.
Get the USB relay with a new 1-year Vigil licence — or renew the licence you already have.