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DHCP clients over Wi-Fi Accessing DHCP server on different interface

Hey All,


I have a FortiWiFi 60D  that we recently moved to a different location with a different phone service. I changed the 'switch mode' to Interface, created a new interface going to Physical Port 7 on the FortiWiFi to be under the subnet and enabled DHCP with the range in the .20s.

I have everything that is plugged into physical Ports 1 and 2 on the FortiWiFi combined with the Wifi SSID on a software switch to go under the subnet and enabled the DHCP server to provide addresses in the 3.0 subnet.


Most clients are connecting fine and going to the proper DHCP server but for some reason there are a couple of WiFi DHCP clients that should be going to the subnet that are somehow being assigned the 20. gateway and a 20. address. 


I've tried getting the user (on a Windows 10 PC) to forget and reconnect to the SSID, I've cleared the DHCP lease to the PC and had him reconnect and tried to give him a reserved address under the proper interfaces DHCP settings to try and force him to connect to the proper interface but all to no avail.


As you can see from the screenshot the WiFi should be connected to the LAN(InternalNetwork) Interface, but there is an iPhone client (that is definitely off of WiFi) being assigned a .20 address.


How is this possible and what do I need to do to fix it?



New Contributor

Figured it out, the Bell Hub 2000 Modem had DHCP turned off but still had leases in its table that were pointing the devices to the wrong subnet.


Thanks to any who read to try and help.


The mac address of smartphones change automatically, this is a function named "Mac Randomization".

Have you try a configure a static dhcp entry for anyone of this clients?

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