Stop Traccar geofence alert spam from GPS jitter
A vehicle parked on a geofence edge can flood your inbox with dozens of enter/exit alerts an hour. The fix isn't a bigger geofence — it's debounced notifications.
Stock Traccar fires a geofence event on every single boundary crossing, and a stationary GPS fix jitters back and forth across that boundary constantly — so one parked vehicle becomes a storm of enter/exit alerts. The fix is debounce with hysteresis: require the vehicle to stay inside or outside for a set time before the notification fires, so you only get the real crossings. Traccar Plus adds exactly this as a drop-in companion service, with no fork or core patch.
Why raw Traccar geofence events fire over and over
Traccar treats a geofence crossing as a binary, per-position event: the moment a reported position lands inside the polygon it raises geofenceEnter, and the moment one lands outside it raises geofenceExit. There is no built-in concept of "has the vehicle really left, or did the fix just wobble?"
That matters because consumer GPS is noisy. A stationary vehicle doesn't report a single fixed point — it reports a cloud of positions scattered by several metres, drifting with satellite geometry, multipath off buildings, and atmospheric conditions. When that cloud straddles a geofence boundary, successive fixes fall inside, then outside, then inside again. Each flip is a fresh event, and each event is a fresh notification.
The result: one parked vehicle, dozens of alerts
The worst offenders are the most ordinary situations:
- A vehicle parked on the edge of a depot or customer geofence, jittering across the line all night.
- Slow movement near a boundary — crawling through a yard or a queue that hugs the fence line.
- Tightly drawn geofences where the fence is barely larger than the GPS error itself.
None of these are real comings and goings, but stock Traccar can't tell the difference — so it forwards every flap as an alert. Operators end up muting geofence notifications entirely, which defeats the point of having them. A debounced-notification request for this has sat open on the Traccar repo for years; the maintainer rightly prioritizes the core, so the quality-of-life fix stays unbuilt.
The fix: debounce and hysteresis
The proven answer is to stop trusting a single position and instead require persistence before acting:
- Debounce. After a crossing, wait a short dwell window and only notify if the vehicle is still on the new side when the window closes. A 30-second flicker across the line never fires.
- Hysteresis. Use a slightly larger boundary to confirm "exit" than to confirm "enter" (or a small buffer zone around the line), so a fix sitting right on the edge can't oscillate between states.
Together these collapse a storm of false flaps into the one event you actually care about: the vehicle genuinely entered, or genuinely left. You keep every real crossing and lose the noise.
How Traccar Plus adds this without touching your core
Traccar Plus is an independent companion add-on — not the official Traccar project — that sits beside your existing instance and talks to it over its own API and webhooks. There's no fork, no patched core, and no migration; you upgrade Traccar whenever you like and the add-on keeps working.
It runs as a single docker run container, typically on the same host as Traccar. It watches your geofence events, applies a debounce window and hysteresis you configure, and only then sends the alert — and it can route notifications per user or per group instead of one firehose for everyone. Because it reads through Traccar's API, your tracking data never leaves your own server.
Quiet the geofence firehose
Traccar Plus adds debounced, hysteresis-based geofence alerts beside your own instance — one Docker container, your data stays on your server. Get started in minutes.
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Runs beside your own instance. Your tracking data stays on your server.
FAQ
Why does Traccar send so many geofence alerts?
Stock Traccar raises an event on every boundary crossing, and a stationary GPS fix jitters back and forth across the line — so each flip becomes a separate enter/exit alert. There's no built-in debounce to suppress the noise.
Can I fix geofence spam without forking Traccar?
Yes. Traccar Plus is a separate companion container that talks to your unmodified instance over its API and webhooks. It applies debounce and hysteresis before alerting, so you keep your core untouched and upgradeable.
Does debouncing make me miss real geofence crossings?
No. Debounce only suppresses flaps that don't persist past a short dwell window. A vehicle that genuinely enters or leaves stays on the new side, so the real crossing still fires — you just lose the false ones.