We have deployed a V2110 controller with NAC at a client.
When users connect to the client's SSID they are placed in a Unregistered Vlan that only allows Access to the NAC using Policy Based routing.
When the client finished with the registration process the either the "Web authenticated" policy or the "Registred Guest" policy applies to the user.
Both these Policies apply a "Bridge @ AP" topology.
The result is that once the user registered and the new policy is applied the user would be placed in the the untagged vlan at the AP.
For Andriod and Windows devices this process works fine.
The client connects initially and the unregistered policy and Vlan is applied, the client is redirected to the NAC portal and completes registration.
Once registration is completed the new policy is applied, either the "Web Auth" policy to the "Registered Guest" policy.
The Andriod and Windows devices automatically releases and renew's their IP's.
With the Apples devices (Both MAC and Iphones) receives the new policy but never renews the IP address. Only a manual disconnect and reconnect updates the IP.
It would seem that the Apple devices ignores the "DHCP release/Renew" instruction that is sent to it.
Any idea why?