Currently running 22.214.171.124 code and trying to anchor a 5508 wlan at the DMZ (4400). I have redundant controllers at the DMZ that are created for Internet access only. When I build the WLAN on the local controller, I would like to add both anchors for redundancy purposes. My first question is with two mobility anchors configured "are clients distributed in a round robin fashion or primary secondary fashion"? The next question is can both anchor controllers share the same subnet and just have different interface IP addresses?
it will dynamically load balance between both 4400s on round robin fashion and won't work like active/standby.
Yes, all involved anchors need to have unique interface ip, it doesn't work like hsrp/vrrp. Regards to dhcp make sure you've non overlapping dhcp scope between the anchors(if internal dhcp is used).
Welcome to CSC.
I might also recommend having a different mobility domain name between the anchors and foreign controllers, for the DMZ. This way your foreign controllers aren't sending unnecessary mobility messages to the DMZ anchor.