Proactive Key Caching Does Not Work

[Curtis]

I have added the following line to my WPA2-Enterprise EAP-TLS wicd / wpa_supplicant config:

proactive_key_caching=1

But it does not work. In an enterprise WLAN This should make it so that each time my client roams (or the 8 hr. re-authentication interval is exceeded) to another radio or access point with the same SSID the Wireless Controller caches the key and simply re-keys without re-authenticating back to the RADIUS server. Instead, each time I roam or when the re-auth interval occurs the credentials are sent all the way back to RADIUS. I happen to be the administrator for this particular WLAN and RADIUS infrastructure so I can easily see it in the logs. This does not occur for example on a Windows laptop that supports opportunistic key caching OKC natively. I've also had this working in the past with wpa_supplicant.

Yes I do have the box checked for "Use these settings for all networks sharing this essid".

Here are my specs:

Laptop = MacAir 6,1
Operating System = ubuntu 16.04.1 LTS
Wireless Adapter = Broadcom BCM4360 802.11ac (rev 03)