Set up a collector

A collector is the Watchtower app that checks whether your devices respond. Run it on a Mac that stays on near your devices and can reach the devices you want to check. An Organization can have several collectors, so separate networks can each use a computer with the required access.

When a release is available for your Organization, open Collector and check the processors listed on the Download macOS collector button. Intel and Apple Silicon identifies a download for either kind of Mac; Apple Silicon identifies a download for Apple silicon only. The collector requires macOS 13 or later. The page shows the version and build selected for your Organization. If no compatible download is available, contact your Watchtower contact for the supported installer.

Pair your collector

1. Install and open the supported Watchtower collector on your Mac.
2. In the browser, open Collector for the intended Organization and choose Generate pairing code.
3. Give the computer a recognizable name and paste the code before the timer expires. The collector uses its default Watchtower address. To change it, open Advanced options and enter the address you use in your browser. Choose Pair and start monitoring. Treat pairing codes as private.
4. Return to the browser. The Collector page updates after pairing succeeds.
5. Add or review your devices’ monitoring hosts from the dashboard’s Edit layout view, then check their status. See Devices and Areas.

The pairing-code section appears above your paired collectors, including when restoring one. Pairing codes expire after 10 minutes. If you cannot request another code, complete a pairing or wait for an unused code to expire.

Cover separate Areas or networks

To pair another collector, choose Add another collector. Each collector keeps its own connection and can be revoked independently.

On each collector’s card, check the Areas it covers and choose Add subnet to enter its Subnets, then choose Save settings. The Area list shows its hierarchy and a summary of your selection; Clear removes all Area selections. You can select multiple Areas and multiple subnets (groups of network addresses). Ask your network contact which subnets to enter if you are unsure. Area coverage includes child Areas. Leaving a list empty places no limit on that setting. When both are set, a device must match both an Area and a subnet.

Devices use Automatic selection by default. Watchtower uses the coverage settings to choose a collector. If it cannot choose one, the device shows NO DATA until you resolve the choice. Choose Edit on the device in the dashboard’s List, choose Change next to Collector, pick a specific Monitoring collector, then choose Save device. An explicit choice can use a collector outside its automatic coverage.

Keep results current

Each collector card shows Agent version with the last version and build reported by that collector. Not reported means the collector has not supplied its version. This is separate from the version offered for download; the card’s reporting status shows whether results are current.

The collector checks configured targets about once a minute using their selected monitoring method. Older collectors only support ICMP ping; HTTP and TCP checks require an updated collector. Without new results for three minutes, device evidence becomes stale and shows NO DATA.

Closing the collector window leaves it running in the menu bar. Quitting stops collection. Keep the Mac awake and connected when you need monitoring. Enable launch at login only if you want the collector to start when you sign in.

Current monitoring does not provide a status timeline, uptime report, or monitoring history.

Replace or disconnect a collector

In Collector, choose Revoke collector and confirm to disconnect it from Watchtower. Other collectors keep running. The disconnected app needs to be paired again before it can report new results; restarting it does not reconnect it. A device explicitly assigned to the revoked collector stays unresolved until you edit it and choose another collector or return to Automatic selection. Disconnection alone does not switch a device to another collector.

To use a revoked collector again, choose Restore collector on its card. Open the collector app and pair it using the new code. Its Areas, subnets, and device assignments are retained, but it stays revoked until pairing succeeds. New checks are needed before device status updates. To restore another collector, choose its Restore collector button. The panel switches to that collector; the earlier code remains valid until it expires or is replaced.

To discard a revoked collector, choose Remove collector and confirm. Removal is permanent. Devices explicitly assigned to it return to Automatic selection; if no collector can be selected, they show NO DATA. Other collectors continue running.

If results stop

Check that the collector is running, that the Mac has the necessary network access and permissions, and that you selected the correct Organization. See Troubleshooting.