on 11-15-2013 03:36 AM
We have been steadily upgrading our old AP-61/65/70 abg access points to 105/93H 'n' access points.
As this has happened the number of complaints from linux users has increased.
We cannot control devices that students bring on campus or the operating systems they choose to run.
In my own testing (using a single ap-group so all settings across AP's are the same), my test device was a thinkpad with an intel 1000bgn adapter running Ubuntu 12.04 LTS.
On our captive portal SSID on the 802.11n AP's linux performs fine.
On our dot1x wpa2-aes SSID on the 802.11n AP's linux connects, and the performance is terrible
On our dot1x wpa2-aes SSID on the 802.11n AP's, if I disable the 'n' rates on the linux host, the performance is good.
On our dot1x wpa2-aes SSID on the AP-61, linux performs fine.
On our dot1x wpa2-aes SSID on the 802.11n AP's with a specific USB 802.11n adapter (Ralink & tplink) I am told linux is fine (someone else tested that, I did not observer)
I would like to know if anyone else is having the same issues, or if there are any suggestions for me.
on 11-15-2013 04:21 AM
on 11-15-2013 05:41 AM
For the affected cards. I have asked now to get the card/driver but I don't have enough replies yet, thanks.
intel 1000bgn card is affected
intel wireless 5100agn card is affected
on 11-15-2013 05:57 AM
We saw an issue that seem similar. I found that the user could connect and stay connected to eduraom but not our campus SSID. The only difference on the two was Bandsteering.
The user disabled 11n (using the commands from the 3rd link below )and then worked fine.
Previous Thread on Community
The user disabled 11n and then worked fine.
Here are the posts-
on 11-15-2013 06:20 AM
Thanks for the suggestions.
On our two SSID profiles, both have band steering. the dot1x profile is eduroam, and the other is our captive portal.
I will try a dev SSID without band steering and see if there is a difference.
For the drivers, a colleague more familiar with Linux than I has I think tried that, but I will double check.
on 11-15-2013 06:42 AM
Disabling band steering on the VAP did not help.
The performance remains poor.
If i do pings to my gateway or to a website
the pings happen fine for a few seconds, and then everything appears to stop for a few seconds. (over and over)
on 11-21-2013 08:06 AM
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 18.104.22.168 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."
11-21-2013 08:20 AM - edited 11-21-2013 08:21 AM
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