We had a problem with Linux users getting connected to our .1x or WPA2 PSK SSIDs but they could only send traffic for a minute or two at best. Upgrading to 6.3.1.0 did not fix the problem (although we did get to start playing with AirGroup). Here is what fixed it for us, right from the Aruba TAC:
"Upon further research found that there was a problem with client linux driver's MPDU aggregation mechanism and it's possible that somehow Linux MPDU aggregation (both in ath9k - atheros and Intel drivers in Linux) suffers this problem.
As a workaround, could you please try to disabled MPDU Aggregation in our controller configuration and please check the status of the client communication.
Under High-Throughput SSID Profile, we have the feature called "MPDU Aggregation". So could you plesae try to disable this " MPDU Aggregation" in the ht-ssid-profile, which will be inside of the SSID profile."
Good luck!
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Here is another workaround **FIRST TRY THE ABOVE - LEAVE THE WORKAROUND..IF NOTHING ELSE WORKING**
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I found a solution for Linux with Intel cards that works for some of my coworkers. Basically, you disable 802.11n speeds and the driver behaves reliably.
Here is a temporary solution that does not survive a reboot.
sudo modprobe -r iwlwifi
sudo modprobe iwlwifi 11n_disable=1
Let me know if the first advise fixed it for u
Under High-Throughput SSID Profile, we have the feature called "MPDU Aggregation". So could you plesae try to disable this " MPDU Aggregation" in the ht-ssid-profile, which will be inside of the SSID profile."