5 wireless controller and roaming security

Question

i want to connect 5 wlan controller to core switch with 470 ap . client must roaming and dont have disconnect. what security must configured

Answer 1

Stephen,
I dropped these questions in the Ask the Expert forum, but they are relevant here:
Our intention is to use the Mobility Group to distribute AP connections among many controllers on several campuses for redundancy in the event of catastrophic failure. With this in mind, several questions arise as to how this can be achieved:
1. What is the formula by which an AP, once it has a list of candidate controllers to join, chooses a specific controller? We understand it has something to do with the number of APs and clients a controller is managing, but what are the quantitative criteria/tiebreakers in the AP decision process? What are the relative/absolute values?
2. If we use DHCP Option 43 to point to the APs to a Master Controller, and subsequently re-assign via the controller GUI the APs Primary, Secondary, and Tertiary controllers, will the APs automatically join the Primary, or do they have to be rebooted? And if rebooted, will these WLC assignments override the DHCP Option 43 if not changed?
3. In the above setup, will the AP stop searching for available controllers if the Pri/Sec/Ter WLC assignments fail? Can other, unassigned controllers in the Mobility Group provide a connection for an AP? Or is N + 1 + 1 the limit?
4. Assuming the AP tries them in sequential order, can we place all WLCs in a Mobility Group inside Option 43, or is it limited to 3 entries like the controller-based assignment?
Thanks for any assistance,