Quick Setup - Start Here

If you are reading this, you have already installed Device Sentinel and added it to Home Assistant. From the moment you clicked "Submit," the integration started quietly watching every device in your registry.

Now, we get to make it yours. Device Sentinel is built to monitor physical hardware, but Home Assistant integrations don't always declare their virtual devices or helper entities correctly. Right now, it's observing everything to help you build a pristine system.

The goal of this guide is to help you shape your setup so that Device Sentinel only ever interrupts you when something genuinely needs your attention.

What to Expect: The First Two Weeks

Device Sentinel doesn't force a one-size-fits-all timeout on your home. Instead, it learns the unique reporting rhythm of every individual device. That learning takes a little time, so you'll want to expect a bit of initial activity during your first two weeks. How Device Sentinel Learns breaks down the mechanics behind the scenes.

Week One: The Noise and the Purge

Right now, the integration is in observation mode, recording the longest gaps between reports to establish a solid baseline.

During this first week, you might see alerts for things you don't actually care about, or items that aren't physical hardware at all, like ping trackers, mobile companion apps, or wall tablets permanently plugged into power. This is entirely normal.

Your main goal in Week One is simply to clear out this noise using the Exclusions and Muting screen. If it isn't physical hardware that can fail in your house, exclude it. If you don't care if it goes quiet, mute it.

Week Two: Freeze Detection Arms

By the start of week two (day 7), Device Sentinel has gathered enough history to arm Freeze Detection for your fleet. If a device goes silent past its newly learned window, it will be flagged.

You might encounter a few false positives this week as the system encounters unusual gaps for the first time. Don't worry, the learning process is ongoing, and when devices recover, their windows adjust automatically.

Your focus in Week Two is to continue muting naturally intermittent devices (like a car sensor that leaves the driveway) or gently adjusting your Freeze Detection sliders if a specific class of devices feels too sensitive.

By the end of your second week (day 14), the rhythms have settled into place. From that point on, if Device Sentinel tells you a device is frozen, you can trust it completely.

Configuring Your System

The configuration menu is designed to flow smoothly from top to bottom.

1. The Three Enable Buttons

Before tweaking any sliders, navigate to the main Device Sentinel integration page in Home Assistant (where you see your main device card and its entities). The Device Page covers everything you'll find there.

Many integrations ship their diagnostic entities, like battery levels, signal strengths, and last-seen timestamps, disabled by default. Device Sentinel can't monitor what it can't see. We provide three simple buttons to turn these on in bulk across your system:

• Enable Battery: Turns on battery percentage sensors for your watched hardware, making low and falling battery tracking possible.
• Enable Signals: Turns on signal strength entities so you can monitor your radio mesh.
• Enable Last Seen (the important one): Turns on the last_seen entity wherever supported. This is the single most effective action you can take for fast, reliable freeze detection.

Why Last Seen matters: Freeze detection looks for state changes. A door sensor might only change state (open/close) twice a day, and its battery might only drop 1% a week. If those are your only enabled entities, Device Sentinel learns that a 12-hour silence is normal. If the sensor dies right after you close the door, you won't hear about it for half a day. However, with last_seen enabled, the device updates every time the coordinator checks in (often every few minutes). Device Sentinel learns this short interval instead, catching a freeze in minutes rather than hours.

Go ahead and press all three buttons now.

2. Notifications and Daily Brief

This screen controls who hears about a problem, and when. It splits your notifications into instant alerts and your daily summary.

A quick tip: Skip High-Priority targets for now.

Until you've cleared out the initial noise during your first two weeks, you don't need instant pushes for every detail. Even after your system is fully tuned, ask yourself if an alert is truly necessary at 3:00 AM. For everyday peace of mind, the Daily Brief and your dashboard card are more than enough. Reserve high-priority alerts strictly for mission-critical setups like vacation home security or water leak detectors.

Set your schedule:

Instead of relying on instant interruptions, lean into Quiet Hours and the Daily Brief.

1. Set your Quiet Hours (for example, from 10:00 PM to 7:00 AM).
2. Set your Daily Brief to publish right at the end of your quiet hours (e.g., 7:00 AM).

The Daily Brief covers the preceding 24 hours, keeping overnight network events neatly bundled together in one readable report.

Links in Reports:

Device names in the HTML reports can link to their device page, which saves hunting for a sensor called "Temperature & Humidity" when you have nine of them. The choice is None, Internal URL or External URL, and each one shows the address it would use.

Default is "None". A report is a file you might share or attach to an issue. Keep this in mind when setting this.

3. Exclusions and Muting

This screen is your primary tool for a clean, quiet dashboard. It offers two distinct approaches, and understanding the difference is key: Excluding discards data. Muting silences alerts.

When to Exclude: An excluded integration or device is entirely ignored, never watched, and never recorded. Use this for software integrations (spook, ping), mobile app trackers that leave the house, or misbehaving smart TV integrations that report unavailable instead of off when powered down.

When to Mute: A muted device is silenced from your reports and alerts, but it is still watched and tracked in the background. Device Sentinel keeps recording its history so that if you ever unmute it down the road, its data is waiting with zero relearning required.

4. Low Battery

Device Sentinel evaluates batteries on two fronts: a flat percentage threshold and a predictive falling trend.

While you can adjust the flat Low Battery threshold (defaulting at 15%), the real magic lies in the Days Till Empty Warning. Lithium coin cells (like CR2032s) hold near-full voltage for their entire life and then plunge off a cliff in days. By watching the rate of decay, Device Sentinel catches that drop well before the device dies.

5. Signal Strength

Signal monitoring is experimental. Everything is recorded and charted, but ordinary weak links won't trigger phone alerts yet while we refine the predictive logic. The one exception is a link stuck at a rail value, a false reading rather than a weak one, which does notify. You can use The Signal Report to review your mesh health at any time.

6. Freeze Detection

This screen lets you tune the grace periods added to your devices' learned rhythms using the Delta Low (fast devices) and Delta High (slow devices) sliders.

Leave these alone during Week 1 and let the system learn. If a specific class of devices feels too sensitive during Week 2, you can gently adjust these to be more forgiving.

7. WiFi

When your Wi-Fi network drops, dozens of smart plugs can go quiet simultaneously. Device Sentinel detects this core network event and reports it as a single incident rather than flooding you with dozens of individual device faults.

It accomplishes this either by listening directly to your server's wireless adapter or by reading supported router integrations (like UniFi or TP-Link). Either path works on its own.

8. Advanced

Most users can leave these settings at their defaults. Four are worth knowing about:

• Storage Write Interval: How often routine data moves from memory to disk. Set it to 30 to 60 minutes if Home Assistant runs on an SD card, to maximize its lifespan. On an SSD, leave it at 15 or drop it to 5.
• How Much History to Keep: 30 days on an SD card keeps the footprint small. 90 days is the default and is enough to watch a battery decay across a season. Lowering it takes effect at the next midnight, so a mistake can be undone before anything is lost.
• Maintenance Window in Minutes: How long Maintenance Mode stays open once you press the button. It defaults to 10 minutes; raise it if your repairs usually take longer.
• Data Trim: At the foot of the screen, the pickers that erase a device's or an integration's learned history. Use them when support asks, or when you know a record has gone wrong and you want it to start over. A backup is written first, and if that backup cannot be written, nothing is deleted.

9. Extended Diagnostics

If you'd like to help improve support for emerging hardware or routers, this screen lists whatever it finds on your system that support is still being built for. A house with no Z-Wave is never asked about Z-Wave.

Contributing takes four steps:

1. Tick the hardware you would like supported.
2. Let it run for about 48 hours, so the readings cover normal behavior rather than one moment.
3. Download your diagnostics: Settings > Devices and Services > Device Sentinel, the three-dot menu, Download diagnostics.
4. Open an issue on the repository, attach the file, and say what you would like built.

Nothing is transmitted anywhere. The readings sit in a file on your own system, and they reach anybody else only if you attach that file yourself.