Higher Education

Question: is there a way to "tone down" the aggression of the client match function?

 

I have some users in specific areas that complain about connectivity issues yet when I use my gear its fine. I take a look at Airwave diagnostics for their users and I see a $&*t-ton of client match bounces from 2.4 to 5GHz and back. Some of them I have been able to placate by having them disable 5GHz on their devices. Others (i.e. iPhone users, iPhones are The Devil!) cannot disable 5GHz on their phones (that I know of) so they continue to see the issue.

 

It's like working with a wireless Tigger - bounce bounce bounce bounce....

 

Thoughts? Stories? Anecdotes?

We've seen some similar issues.  We are still new to Aruba (installed last fall on our campus) so we have been tweaking (twerking?) a number of settings including min/max EIRP and AP placement.  Following some of the guidelines that are out there did help, especially regarding min/max EIRP settings.  See this post for some useful info:

 

http://community.arubanetworks.com/t5/Unified-Wired-Wireless-Access/Client-Match-Configurations-What-Are-Best-Practices-to-Address/td-p/190131

 

That said, we still run into devices every now and then that appear to be aggressive in their behavior of trying to connect to other APs for whatever reason.  My semi-educated guess is that client match eventually gives in and moves the device to another AP, or the device's own behavior of trying to connect to other APs aggressively, causes dropped connectivity for the user.

 

I also suggest you read this doc:
http://community.arubanetworks.com/aruba/attachments/aruba/Aruba-VRDs/28/1/RF%20and%20Roaming%20Optimization%20for%20Aruba%20802.11ac%20Networks.pdf

Sent from my iPhone

@ victorfabian - Thanks again for pointing me in the right direction. I am setting up one of my building with the recommended optimization settings. However I cannot find where to adjust the Transmit Power PER BAND. All I can find both GUI & CLI is the MAX & MIN EIRP but I don't know which band (2.4 or 5GHz) that is setting.

 

So I would like to set the 5GHz to 15/18 and the 2.4GHz to 6/9  as per the optimization recommendations but cannot find where those specific commands are.

 

Help me Obi-Fabian-Kenobi... your my only hope....

See this example :

1- Create an ARM profile per band 

2- Create a Radio profile per band

3- Assign ARM profile based on the band

 

 

 

rf arm-profile "BUILDING-A-11A-ARM-PROFILE"
40MHz-allowed-bands None
no 80MHz-support
cm-band-g-max-signal 10
cm-steer-timeout 3
cm-lb-client-thresh 30
cm-sticky-snr 18
ideal-coverage-index 6
free-channel-index 40
backoff-time 1800
error-rate-threshold 70
error-rate-wait-time 90
!
rf arm-profile "BUILDING-A-11G-ARM-PROFILE"
no 80MHz-support
max-tx-power 12
min-tx-power 6

cm-band-g-max-signal 10
cm-steer-timeout 3
cm-lb-client-thresh 30
cm-sticky-snr 18
ideal-coverage-index 6
free-channel-index 40
backoff-time 1800
error-rate-threshold 70
error-rate-wait-time 90

!

rf dot11a-radio-profile "BUILDING-A-11A-RADIO-PROFILE"
arm-profile "BUILDING-A-11A-ARM-PROFILE"
!

rf dot11g-radio-profile "BUILDING-A-11G-RADIO-PROFILE"
spectrum-monitoring
arm-profile "BUILDING-A-11G-ARM-PROFILE"

!

@ victorfabian - again proving why you are the Master and I am yet a Padewan...

@ victorfabian - am curious, why no 80MHz channel support?

80 MHz channels are not recommended in most environments due to channel availability.

Yes you can, but I would work closely with TAC when changing any ClientMatch
thresholds.

@ jwhitaker@transy.edu - I like the way you twerk it, No Diggity (that's right, twerking AND and 80's song reference in one) and thanks for the link, I'll check it out.

 

@ sportmonkey - I don't hate you even though you tread upon the Dark Side... Otherwise thanks for your insight, much appreciated!

 

@ cappalli - Always good to hear from you :-) and roger that, will take it under advisement.

 

@ mnaylor - Thanks for the input, much appreciated

@americanmcneil phew :) 

 

Be interested how you go forward with this and details of any findings if you "tune" your client match. 

We are upgrading to 6.4.2.7 on Monday so hopefully this will improve things further for us.

 

Something i have noticed, We use AP225's in our library building and they're only about 5 metres apart from each other(as we need to deal with the denisty,loanable laptops and students with more devices)also open planned. We tended not to see an issue with client match here...

 

Sadly cost and layout of other areas/buildings wouldnt allow us to do this across campus

Sportmonkey,

 

You have access points at 5 meters apart?  Is this everywhere in the library?  That is probably too close!

 

@ cjoseph

 

Yes looking on Airwave i think i was abit out on my measurements(Don't all guys suffer with this ;) )

We do have them more closely packed together than other areas.

sportsmonkey,

 

I would do a "show ap arm state ap-name <name of ap>" to see how many access points a single AP can see.  You could be causing too much contention.

 

@ victorfabian - Thanks for the link to that PDF! Good stuff so far! Kudos coming your way sir!

Output

Almost all of your access points are at full power.  That will cause numberous problems and they should not be configured that way.  Please consult the entire document that Vfabien posted above here:  http://community.arubanetworks.com/aruba/attachments/aruba/Aruba-VRDs/28/1/RF%20and%20Roaming%20Optimization%20for%20Aruba%20802.11ac%20Networks.pdf

 

Clientmatch will not improve your environment if your power is too high.

Will look into this, to be honest we havent received or had any problems with this building using that current set up but thank you for the heads up.

Sportmonkey,

It looks like the majority of your access points are on DFS channels, which means your contention or issues would mainly be relevant only to clients that support dfs. That observation is only for that output.

Hi,

 

I have seen the same, but for very random devices. One iphone might be fine(ie mine, don't hate me) but in the same spot an end users will be flapping between bands and APs. Before we move to 6.4.X.X we had "tuned" our wireless for each AP-group. Each of our buildings are very different in materials and layouts so we had different tuned set ups, either using station handoff, RSSI wait and RSSI threshold values. This work very well. On upgrading to 6.4 issues started to creep in. We tested 3000 student halls room with 6 devices at both desk and bed locations using our pre 6.4 "tuned" settings and we had it spot on, but after upgrading and using client match students noticed problems, we had to increase AP numbers and adjust our AP locations to resolve these issues.

 

I believe client match has improved during the development of 6.4 but there are still issues that i notice where devices take a few moments when client match is doing its thing. Also i think where we see a ton of different devices on various levels of OS versions doesnt help poor old cleint smash ;)

We have been dealing with similar issues since our Aruba rollout last summer. Some clients seem to flip-flop every minute. Even turning down the EIRP to (and below) Best-practice settings the issues persist.  Multiple visits by our local reps and multiple hours on the phone with TAC have helped, but the problems remain.

It would be great to see this addressed as I fear the client-match magic may be the root of many user complaints.