LEDs and Buttons

The source material this page replaces covers the LED and button configuration of a NETGEAR WNDR3800 running OpenWrt, including custom wifitoggle software and manual LED trigger configuration. The UDM-SE has a significantly different hardware design and all LED behaviour is managed by UniFi OS without requiring any custom configuration.

UDM-SE front panel

The UDM-SE front panel has a single multi-colour LED ring around the UniFi logo, a USB-A port, and a power button.

LED ring

The LED ring communicates the device status via colour and animation pattern.

In normal operation the LED should show solid white. Yellow indicates something worth investigating: navigate to https://10.1.0.1 and check the dashboard for alerts.

Disabling the LED

The LED is bright enough to be noticeable in a dark room and in a rack environment it serves limited purpose once the device is configured and running.

Navigate to UniFi OS > System > LED Settings. Set the LED state to Off to disable it entirely, or set it to flash only on alerts.

Alternatively, configure it via the UniFi app on mobile under the device settings.

USB-A port

The front USB-A port can be used for:

• USB storage: for UniFi Protect video recording if the HDD bay is not in use
• USB modem / LTE failover: some USB LTE modems are supported for WAN failover
• USB-A pass-through: general purpose, for anything UniFi OS supports

For a standard homelab setup without Protect or LTE failover, the USB port is unlikely to be in regular use.

Power button

The power button on the front panel has three behaviours depending on how it is pressed:

Short press (less than 2 seconds): No action. Prevents accidental power-off.

Press and hold (2-5 seconds): Graceful shutdown. UniFi OS shuts down cleanly before power cuts. Use this for planned maintenance shutdowns rather than pulling the power cable.

Press and hold (more than 5 seconds): Initiates a factory reset. The LED ring flashes white rapidly. Release and wait for the device to reboot to factory defaults. This erases all configuration.

The factory reset hold time is long enough to be deliberate but short enough to happen accidentally if the button is pressed and held while moving equipment. Know where the button is and be careful around it.

UDM-SE rear panel

The rear panel has the WAN ports, LAN ports, and a reset pinhole.

WAN ports

For a standard home internet connection, use WAN2 (the 2.5GbE RJ45 port) with an Ethernet cable to the ISP modem or ONT. If the ISP provides a fibre handoff with SFP+, use WAN1.

Both ports can be active simultaneously for dual WAN with failover or load balancing. Configure this in Settings > Internet.

LAN ports

The six PoE ports (LAN3-8) can power UniFi access points, IP cameras, VoIP phones, and other PoE devices directly from the UDM-SE without a separate PoE injector or switch.

The two PoE+ ports (LAN1-2) provide higher power output for devices that need it: some UniFi access points and high-power cameras require 802.3at rather than 802.3af.

The 10G SFP+ LAN port (LAN9) is for connecting a downstream switch at 10G speeds.

Console port

The rear panel includes a RJ45 serial console port. This provides direct serial access to UniFi OS for recovery scenarios where network access is unavailable. Connect with a USB-to-RJ45 console cable at 115200 baud.

This is rarely needed but worth knowing about. If the network configuration is changed in a way that locks out browser access, the serial console provides a way back in without a factory reset.

# Connect via serial console from the desktop
screen /dev/ttyUSB0 115200

# Or using minicom
minicom -D /dev/ttyUSB0 -b 115200

Reset pinhole

The rear panel has a small pinhole reset button. Behaviour matches the power button hold:

Press less than 5 seconds: Soft reset, restarts UniFi OS without clearing configuration.

Press and hold more than 5 seconds: Factory reset. Erases all configuration. The LED ring flashes to confirm.

For recovery from a misconfiguration, try the soft reset first before committing to a factory reset.

Access point LEDs

Adopted UniFi access points have their own LED status indicators. LED behaviour is consistent across the access point lineup.

Access point LEDs can be disabled globally or per device. Navigate to UniFi Devices, select the access point, and toggle the LED setting. In a home environment where access points are visible on ceilings or walls, disabling the LED avoids a persistent light source in occupied rooms.

Managing device LEDs globally

To disable LEDs across all UniFi devices at once, navigate to Settings > System > LED. Set the site LED mode to Off. This applies to all adopted devices including the UDM-SE, access points, and switches.

Useful for a home deployment where the devices are visible and the LEDs serve no practical purpose once everything is configured and running.

The factory reset procedure is permanent and immediate once the LED confirms it. There is no “are you sure” prompt. Keep the configuration backup from the Router Setup section current so that a factory reset is a two-hour inconvenience rather than a full rebuild.