Upgrade from 7.0.220.0 to 7.2.103.0 - Terrible client performance

[wirelessdeploy]

After upgrading, ping times from clients has gone from ~10ms to ~2500ms. I have a Cisco 7500 Flex controller, when running controller code version 7.0.220.0 client performance was as expected. When using code 7.2.103.0 performance is terrible. I have tried upgrade to 7.2.103.0 and clean configuration (reset) with 7.2.103.0 with the same results.

I have tested using 3502i APs with the signal metrics (from AP) reported by the clients (all testing close to these figures):

Signal Strength   : -48 dBm

Signal to Noise   : 49 dB

AP's are in HREAP/Flex mode. The WLANs use HREAP/FlexConnect local switching. I have tested WLAN's with WPA2-PSK and 802.1x/WPA2 with the same results. I have tested several clients\operatign systems , laptops, ipads, iphone. All experience consitent poor ping latency peformance on both 2.4Ghz and 5 Ghz when using controller code 7.2.103.0.

I have switched between 7.0.220.0 and 7.2.103.0 several times and the results are consistent; good performance on 7.0.220.0 and terrible performance on 7.2.103.0. I would like to use 7.2.103.0 for its enhanced FlexConnect features but this is a real show stopper. Any ideas?

[Justin Kurynny]

wirelessdeploy,

If your testing results are this solid and you've been able to do clean configs on both versions of code, then what you have here is a reproducible problem that TAC needs to know about.

The sooner it can be addressed as a code problem, the sooner it will get fixed. You may even find that it's been found already and it's being addressed.

If it turns out to be a bug then either way, you can always ask for special file access to an intermediate non-public engineering release as soon as they have one available.

I know "Call TAC" is not the answer you're looking for, but this is one of those times that it makes a lot of sense to do so.

Please keep us posted. This seems like a pretty significant issue.

Justin

[Surendra BG]

Hi,

am currently working on this case.. Wirelessdeploy, i guess you opened up a case as well with us and i am working on the exact similar issue.. please revert back to me if you have opened up the case and i am looking for some outputs!!

Regards

Surendra

[tkekalainen]

Hi,

I am making a new installation with 5508 controller and 1142 AP:s. Just upgraded to 7.2.103.0 and about to install AP:s. Is this performance problem expected with my setup also? Or should I just continue with my installation and see the results myself? I'm going to use Flex/H-Reap mode with my AP:s.

BR,

-tomi-

[chopra.harish1]

Hi Tomi,

This kind of issue happens very rare. You should go ahead and install your APs. This may also happen incase of R&S issue when deploying AP's in Distributed mode. But if your R&S is going smooth then deploying APs shouldn't be any issue. Good luck and update us back if required.

[Surendra BG]

Hi All,

here is the bug what we are hitting and here is the workaround as well

http://tools.cisco.com/Support/BugToolKit/search/getBugDetails.do?method=fetchBugDetails&bugId=CSCty17976

high latency with wireless N clients on 7500 WLC running 7.2 code.

Symptom:AP3500 performance for 802.11n clients decreasing when connected to  WLC 7500. Other WLC platforms are not affected.Conditions:Workaround:Run the following commands to disable AMPDU schedulerconfig 802.11b 11nSupport a-mpdu tx scheduler disable config 802.11a 11nSupport a-mpdu tx scheduler disable

Regards

Surendra

[Leo Laohoo]

Thanks Surendra. 

[Vinay Sharma]

Thanks Surendra for sharing this useful information 5+

Vinay Sharma

Community manager

[Vinay Sharma]

This document is generated from the above discussion :-

https://supportforums.cisco.com/docs/DOC-24093

Thanks,