Check inform URL, DNS, firewall ports, VLANs, and Layer 2 vs Layer 3 adoption before opening a ticket.
What if I can't adopt a device?
If a UniFi gateway, switch, or AP never appears — or stays stuck on Adopting — work through these checks first.
Quick checklist
- Factory-reset the device if it was on another controller.
- Confirm the device has DHCP and can reach the internet.
- Verify DNS resolves your i2unifi controller hostname.
- Check firewall rules allow outbound HTTPS and STUN to the controller.
- For remote subnets, set the correct inform URL (Layer 3 adoption).
- On switches, confirm the port VLAN profile allows management traffic.
Common symptoms
| Symptom | Likely cause |
|---|---|
| Device never appears | Wrong VLAN, blocked ports, wrong inform URL |
| Stuck on "Adopting" | DNS failure, MTU issue, insufficient PoE |
| Adopted then offline | Gateway change, routing, or duplicate IP |
Adopt in order
Start with the gateway, then core switches, then access points — one device at a time during initial rollout.
Still stuck?
Open a support ticket with device model, firmware, site name, and a screenshot from Devices or Topology.
- Adopting UniFi Devices — full Layer 2/3 steps
- Double NAT and ISP Modem Setup — if your modem still routes