Roaming prediction 5Ghz

[Pietro Corti]

Hi,

with vWLC 8.0.x and 8.1.131 WLCCA roaming prediction show good roaming between AP in both 2.4 and 5 Ghz (green)

I now have updated vWLC to 8.5.120 (without any change in AP position, channel and operating power) and roaming prediction works as for previous firmware release for 2.4 Ghz but I have Always red alert for 5 Ghz band (Not a neighbor).

Is it a bug of WLCCA or I miss something ?

Thanks a lot

[Scott Fella]

I think you would need to look into this more yourself. You change code on your vWLC from 8.0 to 8.5. That is a major change and things do change that may or might not work well for your environment. Look at what is degrading and perform some tests to see if the data being provided is accurate. The WLCCA takes output from the controller, so it’s the data the controller has. Also, it’s best to stay away from MR1/MR2 and wait for MR3 at least if your testing in production.

[Pietro Corti]

Hi Scott, thanks for your reply.

I tried 8.2 , 8.3 and 8.4 with same issue. This because I need to add 2 more AP 2800 series not supported in 8.0.

I'm doing some test out of working days (it's easy to go back to the previous version with vmware snapshot) and actualy I have voice roaming issue in 5GHz band with 7925 phone.

[Scott Fella]

I don’t know what you are seeing, but is the issue flags specific AP’s like the new 2800’s or even your existing. Are you enabling k/v/r?

[Pietro Corti]

Hi Scott,

the issue flags all 2700 amd 2600 existing AP and only for 5GHz frequency.

I have an SSID for Cisco 7925G voice devices on 802.11a that work very well with 8.0 and 8.1 Virtual Wireless Controller.

Upgrade to 8.2, 8.3 8.4 or 8.5 destroys roaming only on 802.11a band.

WLCCA help me to see that there is no roaming between AP.

So there will be some configuration issue upgrading from 8.0 (or 8.1) to firmware release that support 2800 AP

[Scott Fella]

What I think you need to look at when upgrading is the stable code. As of right now, 8.2.x is what is suggested. Take a look here as there were many issues affecting 2800/3800.

https://www.cisco.com/c/en/us/support/docs/wireless/wireless-lan-controller-software/200046-tac-recommended-aireos.html

You should run a diff from your existing config to the upgraded config to make sure values haven’t changed and also take a look at new configuration items that might be enabled that you may need to disable.

Once you choose a code version, test a few access points where you sit, swap out some of your existing for the new AP’s and see if roaming works and just overall experience.

[Pietro Corti]

Hi Scott, 

thanks for your suggestions,

I've created a new VM with 8.2.166 , configured as for 8.0 production VM (same parameters, same WLAN etc) and also I've create an upgrade of running VM (I can switch easy with VM snapshot out of working hours to do test tasks).

I only usemix of 2600 and 2700, not the 2 new 2800 AP.

What I can see is that 802.11a works very well with 8.0 (good voice coverage on filed , green voice roaming prediction in WLCCA and also on prime 3.3 heatmap).

When I switch to 8.2 (upgraded VM or new VM) I have a slight roaming performance on 802.11a, still same heatmap on prime but WLCCA show me no roaming prediction (between near AP "not a neighbor" and red flag).

With 8.0 roaming prediction is green.

So my ask, to better understand what happens from 8.0 and 8.2, is to better know what config parameters WLCCA use to roaming prediction.

I checked side by side and there are no differences between the two configurations.

With show 802.11a the only added parameters in 8.2 are :

A-MSDU Max Subframes ........................ 3
A-MSDU MAX Length ........................... 8k

not present in 8.0.

[Javier Contreras]

HI Pietro

Could you send me unicast the initial and new sh run files, and show me the problem you see there?

Thanks.

[Javier Contreras]

Hi Pietro

as discussed over email:

Basically:

1. The AP order in one file, does not match the other, this means that AP21 is #51 in one file, and #54 in another
2. When you change the selected config set, the roaming prediction tool will use the AP ID/list from the 8.1, with the AP order for the file in 8.2, causing that all the nearby information is used from the wrong AP

Solution:

If using the roaming prediction tool, load only the file you are interested, and select the Aps from there.

Tested with 8.2 file, it works

[Javier Contreras · Accepted solution]

Adding on top, it works for 2., but fails for 5 GHz

problem fixed, it will be on  next WLCCA post

regards