Device online

The Device online check reports whether a device is currently reachable. Unlike most checks, it does not run on the device: your octoja instance evaluates it from the live connection state. It therefore still reports a result when the device is switched off or disconnected from the network, and you can assign it to any device, including network devices without an agent. It runs every 5 minutes by default, and additionally right away when an agent connects or loses its connection.

When octoja considers a device offline, which grace windows prevent false alarms, and how to tune notifications is explained in Get Alerted When a Device Goes Offline.

Prerequisites

For a network device without an agent, the check needs a reachable monitoring asset that probes the network device's online state. See the network devices reference for how this works.

Steps

1. Go to Devices and open the device you want to monitor.
2. Click the Checks tab → Add Check → Device online.
3. Click Add Check.

To roll the check out to many devices at once, add it to a config package — see Assign checks with config packages. To be notified of an outage, attach an alert configuration to the check — see Set up alerts for a check.

Settings

The check has no settings and no thresholds. How many offline results are needed before anyone is notified is set in the alert configuration.

Results

The result shows Online or Offline and when the device was Last seen. If there has never been any contact, it shows never.

The check's history starts with the Uptime: a bar across the recorded period with the share of time online and offline as a percentage. Each result holds until the next one, so a segment is as wide as the time the device spent in that state. Below, the history lists every result with Time and Status. Clicking a segment or a row selects that result.

The Availability report card also evaluates this check's history and only includes devices that have the check assigned — see the reports reference.

FAQ

Why does the check show an old result for a network device?

When the monitoring asset of a probed network device is offline, octoja cannot know whether the network device is reachable. The check then skips the evaluation and keeps the previous result, so a failed monitoring asset does not raise an alarm for every network device behind it. The old result does not confirm the current state. Assign Device online to the monitoring asset itself as well.

Does a planned restart trigger an offline alarm?

A brief connection drop falls within the grace window and produces no offline result. If the restart takes longer, put the device into maintenance beforehand with checks paused, for example with the Maintenance mode automation action. While checks are paused, the check records no result.