From Cisco Guide: "Under normal roaming conditions, client devices join a wireless LAN and are anchored to the first controller that they contact. If a client roams to a different subnet, the controller to which the client roamed sets up a foreign session for the client with the anchor controller."
I'm assuming a couple things: 1) You are using the same mobility group name at both locations/controllers. 2) that this shared WLAN/SSID is assigned a local interface at the controller location with different subnets assigned for each location. To the controllers, you just "moved" from one ap/controller to another ap/controller in the same group.
Make sure your mobility groups, specifically software versions, are interoperable given that you said you are running different software versions. Search for Cisco Wireless Solutions Software Compatibility Matrix. The latest was just released.
Try this test:
1) Connect from location A with your mobile device. Note the ip address provided from dhcp_discovery.
2) Don't shut your wireless service off. Just jump in your car and drive to location B. I'm guessing it's not that far...maybe less that the default idle timeout set on your location A controller.
3) At location B, ensure you are connected to the same WLAN again. Verify the ip address you are provided. Is it the same ip address you had at location A?
4) Login to controller at location B
Look for your client ip address in the controller. Specifically look for "foreign export" under role? (i this that's the section but can't confirm as I don't have access to a controller now).
Results should dictate a direction.
//art
