Wireless Access

Hello,

 

we recently migrated one building on our campus from AP-135 to AP-225s.

 

Our old Acer laptops with Broadcom BCM43225 chipsets do not have any problems using the new APs. However, our newer Lenovo ThinkPad T430s have major issues with bad response times, packet loss and intermittent dropouts. The Lenovos use the Intel Centrino Advanced-N 6205 chipset.

 

I found an article in the Cisco support forums that people are experiencing this issue on Cisco WLAN infrastructure as well:

 

https://supportforums.cisco.com/thread/2125425

 

The workaround - aside from a possible driver update on the laptops - is to disable Infrastructure MFP (Management Frame Protection) on the WLC.

 

Is there an equivalent workaround on Aruba as well?

 

Thanks for your help!

I found that the latest driver update from Lenovo fixes the issue. The driver is dated from the September 25, 2013 and the version number is 16.1.3.

 

However, I would have liked to address this issue from the infrastructure side as well.

 

Driver updates on PCs are always a pain and take weeks until every last device gets the software...

Hi,

 

We have similar issues with mixed AP's but the same wlan chipsets and using Ubuntu Linux. Is there any news on this? It seems the only workaround to disable '802.11n' for these models, but of course this shouldn't be the final solution.

 

In our environment not only AP225 but AP105 is affected, so I suppose this is some kind of bug in FW. What are the software version of your controller?

 

 

ipal,

 

Please open a case with support/TAC if you can.  If you report it and we know of a fix, we can give it to you.  If you report it and there is no fix, we can at least find out what your specific issue is and possibly work with Intel on a Fix.  If the issue is entirely in the Linux driver, there may be no fix.  Either way, at minimum, please give us the opportunity to figure it out in parallel with your forum post.

 

Thank you. A case already open for this because this is a secondary
effect of a possible bug in IAP225 FW after we converted the environment
to controller based.

The case number is: 1498048

Regards
Laszlo

We are also experiencing the same issue with our clients with Intel 6205 and Intel 7260 NIC. We have a vareity of other NIC combinations in our environment, all of which are working fine.

It seems like the fix for 7260 will be disabling Quiet IE on the controller. Does anybody have any fixes for the issue with 6205 and AP225?

 

Thanks.

#AP225

Navid,

 

The OP upgraded his drivers and fixed whatever his issue was..and this was almost a year ago.  Did you upgrade your drivers?  Exactly what is your issue?

 

 

Users with Intel 6205 and 7260 NICs suddenly stop passing traffic. They are connected to the SSID and are associated to the AP but they cannot pass traffic. They cannot even ping the default gateway.

I have enabled user level debug for some of the users seeing the issue, basically the client sends a "deauth" request to the network and leaves without specifying a reason. A manual reconnect by the user fixes the issue. We have over 30 offices world wide with a combination of AP 105, 135 and 225. We are only seeing this issue where we have AP225s.

 

Any suggestions is appreciated.

 

Navid.

 

 

#AP225

Navid,

Just to make sure we narrow down the issue:

- Does this happen to all the users in the area at a time or a single user
- What encryption are you using?
- How wide are your channels? (20-40-80)
- What version of Aruba OS are you running.

The quiet IE fix is mainly for users who turn on 802.11k (disabled by default)
If it says the client is sending the deauth, that means the clients is leaving or roaming away for some reason

Colin,

Please find my answers below:

1) This is not specific to one user. We have had 50+ users reporting the exact same issue. All of them on 6205 or 7260 and in buildings with AP225.

2) AES

3) 20 MHz (on both a and g)

4) 6.3.1.5

 

The clinets are not roaming. This happens while they are sitting at their desk. All our 802.11k settings are left to "default".

 

Navid.

#AP225

Navid,

Pick one access point where you have seen the issue and give us the output of "show ap arm state ap-name <name of access point>"

(lsnj-wac02.corp) #show ap arm state ap-name lsnj-3-ap12

AP:lsnj-3-ap12 MAC:18:64:72:dc:f7:80 Channel:11 EIRP:9 Max EIRP:21 Edge:disable
Client Density:0 Valid neighbors: 13 Relevant neighbors: 10 Rx Probe Reports: 488651
Moves(T/S):1430/271 Sticky(T/S):72/6 Bandsteer(T/S):1358/265 Loadbal(T/S):0/0
Neighbor Data
-------------
Name               IP Address      SNR (dB)  Path Loss (dB)  Channel/Pwr  Neighbor Density  Neighbors (R/T)  Relevant
----               ----------      --------  --------------  -----------  ----------------  ---------------  --------
lsnj-3-ap03        172.22.193.100  37        70              11/9         0                  8/10            Yes
lsnj-3-ap07        172.22.193.104  26        79              6/12         0                  8/16            Yes
lsnj-3-ap02        172.22.193.99   25        78              6/12         0                  5/14            Yes
lsnj-3-ap11        172.22.193.108  16        88              11/9         0                  10/18           Yes
lsnj-2-ap03        172.22.193.68   16        0               11/9         0                  10/13           Yes
lsnj-3-ap04        172.22.193.101  34        78              1/12         0                  12/27           Yes
lsnj-3-ap06        172.22.193.103  23        86              11/12        0                  10/12           Yes
lsnj-3-ap08        172.22.193.105  18        88              1/9          0                  6/11            Yes
lsnj-3-ap14        172.22.193.111  21        89              11/12        0                  10/19           Yes
00:0b:86:79:c9:20  -               -         -               -            -                 -                -
lsnj-4-ap04        172.22.193.133  10        93              11/9         0                  13/22            
lsnj-3-ap01        172.22.193.98   22        0               1/9          0                  8/20            Yes
lsnj-3-ap05        172.22.193.102  10        94              1/9          0                  12/18            
Legend: R = Relevant, T = Total,  Neighbor Density = (Overlap/Neighbor's Density/ Overlap to local density ratio/ Overlap to neighbor's density ratio)

AP:lsnj-3-ap12 MAC:18:64:72:dc:f7:90 Channel:149 EIRP:15 Max EIRP:22 Edge:disable
Client Density:0 Valid neighbors: 17 Relevant neighbors: 8 Rx Probe Reports: 521423
Moves(T/S):422/50 Sticky(T/S):345/37 Bandsteer(T/S):0/0 Loadbal(T/S):77/13
Neighbor Data
-------------
Name               IP Address      SNR (dB)  Path Loss (dB)  Channel/Pwr  Neighbor Density  Neighbors (R/T)  Relevant
----               ----------      --------  --------------  -----------  ----------------  ---------------  --------
00:0b:86:79:c9:28  -               -         -               -            -                 -                -
lsnj-3-ap14        172.22.193.111  21        90              153/15       0                  5/20             
lsnj-3-ap07        172.22.193.104  30        81              153/15       0                  8/18            Yes
lsnj-3-ap04        172.22.193.101  28        81              36/15        0                  9/29            Yes
lsnj-3-ap06        172.22.193.103  21        86              48/15        0                  5/16            Yes
lsnj-3-ap01        172.22.193.98   17        90              161/15       0                  7/25             
lsnj-3-ap13        172.22.193.110  8         102             149/15       0                  5/16             
lsnj-3-ap05        172.22.193.102  12        97              161/15       0                  6/20             
lsnj-3-ap11        172.22.193.108  23        91              48/15        0                  5/17             
lsnj-4-ap04        172.22.193.133  9         103             48/15        0                  7/30             
lsnj-4-ap12        172.22.193.141  5         0               153/15       0                  5/16            Yes
lsnj-3-ap02        172.22.193.99   27        86              44/15        0                  2/12            Yes
lsnj-2-ap03        172.22.193.68   8         103             48/15        0                  4/13             
lsnj-3-ap03        172.22.193.100  41        69              157/15       0                  6/16            Yes
lsnj-3-ap08        172.22.193.105  22        87              40/12        0                  6/16            Yes
lsnj-4-ap03        172.22.193.132  9         101             44/15        0                  7/23             
lsnj-3-ap10        172.22.193.107  12        0               40/15        0                  4/14            Yes
Legend: R = Relevant, T = Total,  Neighbor Density = (Overlap/Neighbor's Density/ Overlap to local density ratio/ Overlap to neighbor's density ratio)


(lsnj-wac02.corp) #

Navid,

 

It seems like you have very, very good density.  How far apart are your access points and how many SSIDs are you broadcasting?

 

 

I know the APs are pretty close ! About 40 feet between every two AP on average. We usually broadcast three SSIDs (one 802.1x authenctication for the Corp network and two "guest" SSIDs with PSK auth).

This is just a sample building. We have the same issue at other buildings with AP225s as well.

#AP225

Navid,

 

Okay, we need to get a sampling of your utilization in the Air.  It might be after hours now but let us see the output of:

 

show ap debug radio-stats ap-name lsnj-3-ap12 radio 0 advanced | include intvl,Busy
show ap debug radio-stats ap-name lsnj-3-ap12 radio 1 advanced | include intvl,Busy 

 

Has there been any developments on this? We have recently installed a bunch of AP-225's and the only devices having trouble connecting are those with the Intel Centrino 6205. Have got the latest drivers from Intel still no joy.

The issues that the user had was from almost 3 years ago.  Can you be specific about any issues that you are having?  What do you mean by "having trouble connecting"?  Do you mean it never connects?  What percentage of the time does it stay connected?  Are you using encryption on that SSID?

They cant connect at all and on most occasions can't actually see the SSID's. The SSID's have not changed at all during or following the new AP installation. One thing I will add, after reading the preceeding connects is that I believe the density of these new AP's in these new buildings is way to high. Not my design but mine to manage.

Maybe, maybe not.

How many SSIDs?

What is the distance between APs?

What is the output of "show ap arm state ap-name <name of ap>" of one of those APs?

What is the ARM minimum and maximum transmit power in the ARM profile?

 

3 SSID's

15 to 20 metres

 

(TNE-Wi-Fi-Coo) #show ap arm state ap-name NEI_COO_CLC2_AP

AP:NEI_COO_CLC2_AP MAC:44:48:c1:d8:20:80 Channel:11 EIRP:6 Max EIRP:21.5 Edge:disable
Client Density:0 Valid neighbors: 6 Relevant neighbors: 6 Rx Probe Reports: 19095
Moves(T/S):0/0 Sticky(T/S):0/0 Bandsteer(T/S):0/0 Loadbal(T/S):0/0
Neighbor Data
-------------
Name IP Address SNR (dB) Path Loss (dB) Channel/Pwr Neighbor Density Neighbors (R/T) Relevant
---- ---------- -------- -------------- ----------- ---------------- --------------- --------
NEI_COO_CLC3_AP 172.25.136.99 28 76 1/9 0 5/5 Yes
NEI_COO_CLC1_AP 172.25.136.95 29 71 11/6 0 9/9 Yes
NEI_COO_CLC6_AP 172.25.136.106 38 62 6/9 0 7/7 Yes
NEI_COO_CLC4_AP 172.25.136.97 36 64 6/6 0 8/8 Yes
NEI_COO_CLC5_AP 172.25.136.105 34 66 1/9 0 7/7 Yes
NEI_COO_BG07_125_AP 172.25.136.54 2 102 11/9 0 6/6
Legend: R = Relevant, T = Total, Neighbor Density = (Overlap/Neighbor's Density/ Overlap to local density ratio/ Overlap to neighbor's density ratio)

AP:NEI_COO_CLC2_AP MAC:44:48:c1:d8:20:90 Channel:36 EIRP:18 Max EIRP:19 Edge:disable
Client Density:0 Valid neighbors: 5 Relevant neighbors: 5 Rx Probe Reports: 19079
Moves(T/S):0/0 Sticky(T/S):0/0 Bandsteer(T/S):0/0 Loadbal(T/S):0/0
Neighbor Data
-------------
Name IP Address SNR (dB) Path Loss (dB) Channel/Pwr Neighbor Density Neighbors (R/T) Relevant
---- ---------- -------- -------------- ----------- ---------------- --------------- --------
NEI_COO_CLC1_AP 172.25.136.95 39 79 112/18 0 4/6 Yes
NEI_COO_CLC4_AP 172.25.136.97 33 80 149/18 0 6/6 Yes
NEI_COO_CLC5_AP 172.25.136.105 42 73 157/18 0 5/5 Yes
NEI_COO_CLC6_AP 172.25.136.106 40 111 60/18 0 3/3
NEI_COO_CLC3_AP 172.25.136.99 37 79 44/18 0 4/5 Yes
Legend: R = Relevant, T = Total, Neighbor Density = (Overlap/Neighbor's Density/ Overlap to local density ratio/ Overlap to neighbor's density ratio)

 

ARM a radio: 18 - 12

ARM g radio: 9 - 6

I don't think that density is bad, at all.  Do you have "Drop Broadcast and Multicast" enabled on all of your SSIDs?

After just having a look.... No I don't.

You should enable it on all of your Virtual APS.

Have done that now. Unfortunately these buildings are hours away from me so getting someone to test maybe difficult.

These are our oldest model of laptops and there are very few left in the fleet (including mine)

Mark down the time and date you made the change.  If you have Airwave, see if the Channel Utilization is going down for those APs over time.

Don't have airwave.

The dashboard on the controller GUI has the channel utilization.  Change it so it is only showing 802.11a (5ghz) band.  See how many APs are in the 40 to 50% range.  Do the same thing on the 802.11b/g (2.4ghz) band.

At the site I have been using for testing, All of the new AP's are at 35% to 52% in the 2.4 band.

Same at one of the other 4 new sites and there is actually only 1 client connected at the moment.

The 2.4 will always be more than the 5ghz because there are fewer channels and more cochannel interference.  Fortunately most clients will go to the 5ghz band, instead.

 

What are the numbers for the 5ghz for each site?

 

Take a screenshot of your dashboard before we make any more changes.

 

They are all between 1% and 10% with the majority floating around 5-7%.

I'm not sure if I said this but the device with the the NIC mentioned can walk out of the these building and into a building without 225's and immediately connect to the SSID's.

Are you saying, after making the changes, devices still cannot connect?

 

 Yes. Just had a staff member test a machine and it happily connected to the SSID when in a building with an AP 135 but when the machine was taken into a building populated only with AP225's she couldn't even see the SSID's.

How many SSIDs are you running?  Do you have them hidden?  Are you running DFS channels?

3 SSID's. Not hidden. Default for Australian regulatory domain.

And to follow that up I remote connected to the machine in question last night and check all the settings on the NIC and they are correct.

You should open a TAC case.  It would be difficult to diagnose what is going on from here.

HI Colin, just thought I would let you know I have solved this. In another thread concerning this NIC you advised turning off “Advertise 802.11K Capability” on the 802.11K profile. Not the same issue but a small resembalance. In response to this the other person said they had read somewhere that older Intel NIC's do sometimes have an issue with 802.11K. So I disabled it and now all is fine.

Confirmed that this solution worked for me as well with a test SSID. Now I have to figure out the ramifications of turning off 802.11k site-wide vs. providing wireless dongles for users who have these older intel chips.

 

Does anyone have information on whether it's possible to configure 802.11k on a per VAP basis? Meaning, would I be able to create another SSID that has 802.11k disabled in the areas that need it while broadcasting the standard site-wide SSID on the same AP, or would it remove the feature on the entire AP, regardless of the various VAPs in the AP Group?

You can assign an 802.11k profile for each SSID, so yes, you can turn it off or on.

 

Most clients don't support or leverage 802.11k anyways so you can turn it off without any ill effect.

Thanks Colin,

 

Just wanted to confirm. A large portion of clients on my environment are smart phones (iPhones and Androids). Would roaming be negatively affected if I did this?

 

Best Regards,

Sean

Roaming will definitely work without 802.11k

Hello Ipal,

 

we have 7200 series controllers running ArubaOS 6.3.1.2 - we need Apple Bonjour services, thats why we are on the ED release.

 

As for Windows running on Lenovo T430 series laptops, I found that the drivers from June 2013 or newer do not experience those issues. Any version 15.3.1.2 or newer seems to have fixed that problem.

 

That does not help you running Ubuntu, of course...