Unifi Device Won't Pair? A Guide to Solving Adoption Failures
Setting up a new Unifi access point, switch, or gateway should be a straightforward process, but sometimes devices refuse to pair, or "adopt," into your Unifi Network Controller. This can be caused by a variety of issues, from network misconfigurations to a device being linked to a previous setup. This guide will help you diagnose and resolve the most common Unifi adoption problems.
Understanding the Unifi Adoption Process
Before troubleshooting, it's helpful to know what's happening behind the scenes. When a new or factory-reset Unifi device is connected to your network, it broadcasts a signal to be discovered. The Unifi Network Controller "hears" this signal and lists the device as "Pending Adoption." When you click "Adopt," the controller sends its configuration details to the device. The device then provisions itself and appears as "Online." An adoption failure happens when this communication process breaks down.
Common Causes for Adoption Failure
- Managed by Other: The device is already configured to work with a different Unifi Network Controller. This is common if you're moving a device from one site to another or rebuilding your controller.
- Network Barriers: The device and the controller are on different subnets or VLANs without proper routing, or a firewall is blocking the communication ports (typically port 8080/tcp).
- Controller Inaccessibility: The device cannot resolve the hostname or IP address of the controller.
- Device or Controller Glitches: Sometimes, a simple bug or temporary state can prevent adoption, requiring a reboot of the device or the controller software.
Troubleshooting Step-by-Step
Follow these methods, starting with the simplest, to resolve your pairing issues.
1. The Simple Reboot
Before anything else, try rebooting the Unifi device that won't adopt. If that doesn't work, try restarting your Unifi Network Controller as well. This can clear any temporary state issues.
2. Factory Reset the Device
If the device is showing as "Managed by Other," the cleanest solution is to perform a factory reset. This will wipe its previous configuration and put it back into a discoverable, "pending adoption" state.
- Locate the physical reset button on the device. It's often a small, recessed button that you'll need a paperclip to press.
- With the device powered on, press and hold the reset button for 10 seconds.
- The device's LED light will flash, indicating that it is rebooting and resetting.
- After a minute or two, it should reappear in your controller as "Pending Adoption."
3. Manual Adoption via SSH
If a factory reset doesn't work or you want to avoid it, you can manually tell the device where to find your controller. This is the most powerful method for resolving stubborn adoption issues.
Step A: Find your Controller's "Inform" URL
This is the address the device needs to report to. It's typically http://<controller_ip>:8080/inform. You need to replace <controller_ip> with the actual IP address of the machine running your Unifi Controller.
Step B: SSH into the Device
Use an SSH client (like PuTTY or Terminal) to connect to the device's IP address. The default credentials for a non-adopted or factory-reset device are:
- Username: ubnt
- Password: ubnt
Step C: Issue the set-inform Command
Once logged in, type the following command, using your controller's IP address:
set-inform http://192.168.1.10:8080/inform
Press Enter. The device will attempt to contact your controller.
Important: Immediately after executing the command, go to your Unifi Controller. The device should appear as "Pending Adoption." You must click the "Adopt" button. The device will then connect a second time on its own to finalise the pairing. You may need to issue the set-inform command a second time right after clicking adopt if it gets stuck.
By working through these steps, you can overcome even the most persistent Unifi adoption failures and successfully integrate all your devices into your network.