Fixed Leases in DHCP with Apple Devices

I have found all of my Apple devices (iphone and iwatch) do not advertise a hostname and use a fake MAC address that changes. I understand I can disable this behavior in Apple’s Settings, but I’d like to accommodate it from IPFire if possible. I am wanting my Apple devices to be recognized and kept on the same IP always while connected to IPFire. I have been doing the following:
connect device, record IP, map the IP to a descriptive hostname I make up under Edit Hosts, and set a long lease time in DHCP. For the most part, this works, but sometimes I still see the fake MAC address changed and I have to redo my work for that device.

Would assigning Fixed Leases keep the device from changing MAC addresses? Does anyone have experience with this?

I know nothing about Mac products.
On my Android phone In the connection settings for my home wifi you can set it to use real mac address.
This is for that network only.

You can’t change the behaviour of the Apple OS by means of DHCP server settings.
But you can try to ‘educate’ the Apple device by restrictive server rules.

  • define a fixed lease with the allowed/desired MAC
  • define an empty set of dynamic leases ( start address > end address, f.e. )

The device gets an IP only, if it identifies with the defined MAC. On the other side only devices known by dhcp server get an IP. This complicates the process of adding new devices to the network. ( My usual way: look for the dynamic lease information, make it to a fixed lease )

I have no experience with this but I am pretty certain that having a fixed lease from IPFire will not stop the apple software deciding to change the MAC address.

For this to work then your Apple devices need to have a fixed MAC Address, whether the real physical MAC address or a randomised MAC Address. If the MAC address is changed periodically on the Apple devices then the IPFire DHCP Fixed Lease will no longer get applied.

On my Android device it can either have a real physical mac address or it can have a randomised MAC Address, but once this randomised MAC address is assigned it stays fixed and is not changed over time.

Does the Apple software not have the ability to choose a randomised MAC Address that then stays fixed after that.

If Apple only allows the real MAC address or a randomised MAC address that is periodically changed then you are going to have to choose the real MAC address if you want Fixed Leases to work.

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This is the answer. For some reason, I did not realize that disabling “Private WiFi Address” on the iPhone was specific to that network. I did not want to globally disable this privacy setting, and wrongly thought that this would do that. Thanks.

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I believe it’s supposed to, according to Apple. But sometimes someone will have wifi problems and in troubleshooting, will “forget” the network and rejoin, which resets the MAC. It seems there may be other circumstances where it still changes, that I have not figured out yet. But as I said in my other reply, it was my misunderstanding of how Apple does this that lead me not to try disabling the privacy setting. Thank you.

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I have Apple devices and I ran into the same issue.

The correct (easy!) fix is the Private Wi-Fi Address to OFF as you already know. This disables random MAC addresses.

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You can leave the private MAC address switched on in Apple devices.

This is certainly not crucial in a home network, but you can leave the private WLAN address switched on and set up a fixed IP as described above. At least in my case, the MAC in the corresponding WLAN network always remains the same in the end.

This is right, partly.
The functionality of random MACs includes the selection ‘same MAC in the same WiFi network’. But how is the network identified? What if Apple decides to change this rule?
Fixed leases or even ‘constant’ leases demand an unique identification, which is mainly the MAC. Therefore you should not play with this. In ‘real life’ a frequent change of name isn’t accepted also.