Clarification on how to set up Master - Local design in campus network with different VLANs and IP addresses.
We currently have a Master Controller in one building. We have a Local Controller in another building. The networks are connected with a VPLS that uses the layer 2 management VLAN to manager the controllers and AP's between buildings. The user VLAN for wireless are on different subnets and VLANs in each building that uses OSPF to advertise the routes. DHCP servers are located at each building along with core routing switches with DHCP helper addresses on the core switch for the VLANs. There is a separate internet connection in each building. In this scenario, if the local controller fails how can the master take over but still allow the traffic in the building with a local controller failure to route locally in that building. We are running the 6.5 version of Aruba OS and not 8. What is the best architecture in this scenario?