Bruce Richardson wrote
I understand that you can replicate the accounting data on from freeradius but for this to work obviously the WiFi client's IP address needs to be in the radius accounting data. At the moment it isn't because at the point when the accounting data is sent the client has not yet sent its DHCP request.
Yes many such schemes put the cart before the horse.
Am I correct that to get the IP address into the radius accounting the freeradius server needs to be configured to send out the IP addresses rather than different DHCP server.
Depends on your NAS, and the firewall. As an alternative, some NAS units can send a status update accounting request after their DHCP-snooping or "ip device tracking" facilities notice an IP address. If the firewall will heed these you may be in luck. On some this works perfectly, on others you'll find that old authentication sessions stick around in the switch and continue to send these status updates even when the client has gone and moved to another port/NAS.