Low percentage of active devices per site

Who it’s for

Facility and fleet managers and on-call engineers responsible for a whole site’s device population, asking “is this site still reporting?” and “did a chunk of devices go dark overnight?” — a brief blip in a device or two should pass quietly, but a site-wide drop from a failed gateway, network, or power outage deserves attention. It’s the aggregate counterpart to per-device offline alarms: those catch an individual device dying, this catches many going dark at once without one alarm per device, and it’s most useful on sites with enough devices for a percentage to be meaningful.

What it does

Reads two time-series keys on the target entity — activeDeviceCount and totalDevicesCount — and raises a Critical alarm when their ratio drops below a configurable threshold for a sustained period. The alarm clears automatically once the ratio recovers for a sustained period.

How to set up

This rule reads activeDeviceCount and totalDevicesCount. Pair it with the upstream field that counts a site’s devices:

Active Device Count Per Site verified Dmytro Shvaika

Install this rule on the same “Site” (or similar aggregating) asset that field is installed on, or on its asset profile so every site of that type is covered, including ones added later. Every threshold/duration argument has a default value, so no per-entity setup is required before the rule starts evaluating.

How to customize

• To change the low-device threshold (default 50%) — set threshold as a server-scope attribute on the entity, or change the Default value on the threshold argument.
• To change how long the drop must persist before alarming (default 30 minutes) — set alarmMinutes as a server-scope attribute, or change its Default value.
• To change how long the recovery must persist before auto-clearing (default 10 minutes) — set clearMinutes as a server-scope attribute, or change its Default value.
• To read the device counts from different telemetry keys — change the Time series key on the activeDeviceCount/totalDevicesCount arguments.
• To control where the alarm shows up — toggle the propagation flags under Advanced settings.

See also

For a single device or a single feed, pair this site-level rule with:

IoT Device Offline Alarm verified Dmytro Shvaika

Sensor Stopped Reporting Alarm verified Dmytro Shvaika