I have a 2112 WLC and four 1252 access points in a building and am getting very poor
load balancing / client roaming performance.
We'll commonly see situations with a client unable to associate with an access point that is closest, but rather instead is associating with an access point all the way across the building (and getting poor RF signal, of course) even when an AP that's only ten feet away has perhaps one or two (mostly idle) clients associated with it, as shown in the WLC 2112's web GUI.
It's as if the AP being allowed for the client to associate with is completely random, and even though "Roaming Aggressiveness" is set to max in the client, it hardly ever picks the best candidate.
Additionally, often the clients will get randomly disconnected for no apparent reason at all, and the user has to manually reconnect.
The clients are all Panasonic Toughbooks with Intel 4965AG integrated WiFi interfaces. We're running the latest available Intel ProSET WiFi drivers and application, version 220.127.116.11 (13-Jan 2010).
There is only one single WLAN/SSID defined in the WLC 2112 and all the APs are in the default group assigned to this WLAN/SSID.
I've upgraded the firmware in the WLC to 5.2.193 from the original shipped version (5.1.1), but it has not helped any.