In a design with 2 redundant contollers in the head quarter and small remote sites connected via a WAN link and equipped with AP1030 without controllers, is there a way to configure the AP1030 that the data payload will remain at the remote site not taking twice the way via the WAN link to the controller and back for a communication between 2 clients at the remote site.
Yes. Configure the remote 1030 in REAP mode. The clients will not tunnel back to the central controllers in this mode and you can break out locally to the VLAN and associated IP subnet that the AP is connecting from using L3. Cleients will be assigned an IP addresses from the local DHCP pool of that local VLAN and IP subnet.