Frequently Asked Question
Why does my iPhone appear as a new UniFi device or miss its fixed IP reservation?
QUICK ANSWER
A DHCP reservation follows the MAC address the device presents on that WiFi network. Apple Private Wi-Fi Address can use a different address, and some modes rotate it.
Applies to: UniFi DHCP reservations and Apple devices with Private Wi-Fi Address. Fixed/Rotating choices depend on the OS version.
Work through these checks
- Match the connected identity. On the phone's settings for this specific WiFi network, compare the WiFi address with the current UniFi client. Do not assume the device's hardware address is the address being used.
- Review the reservation. In UniFi Client Devices, confirm Fixed IP Address belongs to the intended current client/MAC and the correct network. Check for an old reservation or another device using the address.
- Choose a stable per-network policy. Where supported and appropriate, a Fixed private address can provide a stable identity while retaining cross-network privacy. Follow the organisation's device policy instead of disabling privacy for every network.
- Reconnect and verify. After an authorised reservation change, reconnect the device and check its issued address and intended access. Record which identity the network policy actually follows.
Confirm the result
The current client receives the intended reserved address and behaves consistently under the chosen per-network privacy setting.
Before going further: Do not copy another device's MAC, disable security controls broadly or treat a new client-history entry alone as proof of an intruder.
If you need help
Include these details in your ticket: OS version, private-address mode, network category and reservation behaviour. Send identifying addresses privately if needed.
Related guidance: Why does UniFi report a duplicate IP address or an unexpected DHCP server?
Updated 261110