A Ubiquiti Cloud Gateway Ultra that restarts or runs hot has a small fanless-looking case with limited airflow, and the usual causes are poor ventilation, an unstable power supply and a software fault. Check where it sits. The Cloud Gateway Ultra is a compact gateway with a small fan on some units, and it needs air round it; if it is wedged behind a television, stacked under other equipment or in a closed cabinet, it will run hot and may reboot to protect itself. Put it where air moves freely, away from direct sun and heat sources, and feel the case:
The checks in more detail
warm is normal, too hot to hold a hand on is not. Power is the next suspect. Use the power adapter or the Power over Ethernet source that Ubiquiti specifies, and avoid plugging it into a cheap extension or a failing surge strip. A UPS with a failing battery causes repeated restarts. Watch the console: in the UniFi Network application, open the device's page and look at the uptime and the logs, which show whether it restarted because of power loss or a software crash. A pattern of a restart at the same time each day suggests a scheduled task or an update.
Check that the firmware and the UniFi Network application are current, since Ubiquiti fixes stability bugs in updates. Too many connected clients or heavy features such as Intrusion Prevention at full speed can load the CPU, so look at the CPU and memory graphs; sustained high CPU with Intrusion Prevention on suggests turning it down. A faulty SFP module or a bad cable can cause link flapping that looks like a restart. Export a support file from the UniFi interface for Ubiquiti, and note the serial number. If the unit keeps restarting with good power and airflow, request a replacement under warranty through Ubiquiti or the reseller.
The Cloud Gateway Ultra handles routing and can also run the UniFi Network application and a few other apps, such as Protect for cameras, on the same unit, and heavy use of these raises the temperature. If you run UniFi Protect on it with several cameras, the extra load is significant, and an external drive is needed for recordings. Turn off any application you do not use. A failed or dirty fan on units that have one makes a noise before the fault shows. Check the logs for out of memory errors, and consider moving some load to another device if the memory is full.
Differential
Likely causes of “Ubiquiti UniFi Cloud Gateway Ultra restarts, freezes or overheats”, and how to tell them apart
- 1
Poor ventilation
What separates it A hot case and thermal restarts
How to confirm Give it free airflow
- 2
Unstable power
What separates it Restarts that match power events
How to confirm Use the correct adapter or PoE source and check the UPS
- 3
A software fault
What separates it Restarts with a crash in the logs
How to confirm Update firmware and the UniFi application
- 4
High CPU from features
What separates it High CPU graph
How to confirm Reduce Intrusion Prevention or other heavy features
- 5
A hardware fault
What separates it Restarts with good power and airflow
How to confirm Request a replacement
Before you touch a setting
Record this first — changing settings destroys the evidence
- When the problem started and what changed
- Any message on the screen
- Whether it happens in every app
- The model and serial number
Try in this order
0 of 6 completedCheck placement and airflow
ReversibleAway from heat.
Check power
ReversibleAdapter, strip and UPS.
Read the device logs
ReversibleIn UniFi Network.
Update firmware
ReversibleAnd the application.
Check CPU load
ReversibleAnd features in use.
Contact Ubiquiti
ReversibleFor a replacement.
Model-specific
What is true of this model and not of its siblings
- Thermal protection
- The unit restarts if it overheats.
- Support file
- Export one for Ubiquiti.
Stop boundary
When this stops being a self-service repair
- !If the steps do not clear it, contact the maker with the model and serial number
- !Back up important data before a reset
- !Check the warranty before paying for a repair
Evidence ledger
Sources behind this answer
Exact questions
Common questions
Why does my Cloud Gateway Ultra restart?+
Heat, power or a software fault.
Is a warm case normal?+
Warm yes, very hot no.
Where are the logs?+
In the UniFi Network application.
Can features cause it?+
Heavy ones can.