IssueTracker

Just going to copy/paste what I put in the Nexus 5 bug page here too since it applies:

I think I figured out what the problem was at least on my end. I was able to create a few differently configured wireless networks to zero in on the culprit.

I tried a few different configurations but one setting consistently caused this issue, which was using AES as the encryption policy for the WPA2 network.

Creating a WEP network with the same name does not cause this issue, so I was able to rule out the similar network names being the cause. COMPANY_Employees, COMPANY_MobileDevices, COMPANY_Guest, etc will all connect as intended if they aren't using AES encryption.

It looks like Lollipop has an issue with WPA2 AES encryption. As soon as I switched to TKIP, I was able to connect quickly and without issue. Hopefully this helps someone else out there while we wait for this issue to be fixed in Lollipop.

Having the same problem TKIP works and AES no connection on my nexus 9

On the Nexus 9 this seems to be a different problem than the one reported in the preview. Here is the logcat output of the failure with verbose wifi logging enabled, I couldn't find a reference to explain what the return codes meant:

11-05 10:49:31.795 E/WifiConfigStore(  450): updateSavedNetworkHistory(): try "Guest"WPA_PSK SSID="Guest" Guest [WPA2-PSK-CCMP][ESS] ajst=128

11-05 10:49:31.795 E/WifiConfigStore(  450):         got known scan result c4:0a:cb:xx:xx:xx key : "Guest"WPA_PSK num: 19 rssi=-90 freq=2437

11-05 10:49:31.795 E/WifiAutoJoinController (  450): Portthru d2:0c:cf:vv:vv:vv rssi=-87 cap [IBSS] is not scored

11-05 10:49:31.795 E/WifiAutoJoinController (  450): ageScanResultsOut delay 40000 size 66 now 1415213371795

11-05 10:49:31.795 E/WifiAutoJoinController (  450): newSupplicantResults size=65 known=18 true

11-05 10:49:31.795 D/WifiNative-wlan0(  450): doString: [STATUS-NO_EVENTS]

11-05 10:49:31.795 D/wpa_supplicant( 5768): wlan0: Control interface command 'STATUS-NO_EVENTS'

11-05 10:49:31.795 D/WifiNative-wlan0(  450):    returned wpa_state=SCANNING p2p_device_address=52:2e:5c:yy:yy:yy address=50:2e:5c:ww:ww:ww uuid=zzzzzzzz-zzzz-zzzz-zzzz-zzzzzzzzzzzz

11-05 10:49:31.795 E/WifiAutoJoinController (  450): attemptAutoJoin() status=wpa_state=SCANNING

11-05 10:49:31.795 E/WifiAutoJoinController (  450): p2p_device_address=52:2e:5c:yy:yy:yy

11-05 10:49:31.795 E/WifiAutoJoinController (  450): address=50:2e:5c:ww:ww:ww

11-05 10:49:31.795 E/WifiAutoJoinController (  450): uuid=zzzzzzzz-zzzz-zzzz-zzzz-zzzzzzzzzzzz split=4

11-05 10:49:31.795 E/WifiAutoJoinController (  450): attemptAutoJoin() num recent config 1 ---> suppNetId=-1

11-05 10:49:31.796 E/WifiAutoJoinController (  450): attemptAutoJoin skip candidate due to auto join status 128 key "Guest"WPA_PSK reason 4

11-05 10:49:31.796 E/WifiAutoJoinController (  450): attemptRoam not associated

11-05 10:49:31.796 E/WifiAutoJoinController (  450): Done attemptAutoJoin status=0

Also experiencing this on N5 LRX21O, connecting to a WPA2 AES PSK corporate network using Cisco access points.

From what I've gathered online this largely seems to be happening to Cisco AP users. I have a Ubiquiti AP at home with a similar configuration that works fine.

This started happening for me on the second developer preview but I didn't look too far into it at the time given the preview status.

I am seeing the following in logcat:

I/wpa_supplicant( 9615): wlan0: Associated with 00:26:cb:ab:c2:a0
I/wpa_supplicant( 9615): wlan0: WPA: CCMP is used, but EAPOL-Key descriptor version (3) is not 2
I/wpa_supplicant( 9615): wlan0: WPA: CCMP is used, but EAPOL-Key descriptor version (3) is not 2
I/wpa_supplicant( 9615): wlan0: WPA: CCMP is used, but EAPOL-Key descriptor version (3) is not 2
I/wpa_supplicant( 9615): wlan0: CTRL-EVENT-DISCONNECTED bssid=00:26:cb:ab:c2:a0 reason=4

The issue seems to boil down to the EAPOL descriptor version being 3, which you can see in the verbose log:
D/wpa_supplicant( 9615): wlan0: RX EAPOL from 00:26:cb:ab:c2:a0
D/wpa_supplicant( 9615): wlan0: IEEE 802.1X RX: version=2 type=3 length=117
D/wpa_supplicant( 9615): wlan0:   EAPOL-Key type=2
D/wpa_supplicant( 9615): wlan0:   key_info 0x8b (ver=3 keyidx=0 rsvd=0 Pairwise Ack)
D/wpa_supplicant( 9615): wlan0:   key_length=16 key_data_length=22

This has potential to be a fairly significant issue for us. Thanks

Wanted to contribute that this issue is only occurring on Cisco APs/AES/Lollipop for me. My connection at home is also WPA2 with AES on a non-Cisco AP and the connection is stable.