Roaming and vWLC

[Denniz]

Hello! I have a vWlc (v 8.10.185.0) and some access points (2802i's and 2702i's). When clients move in the building the clients won't roam from ap to ap. If they do, the client disconnects form the wlan and then reconnects instead of roam. What is the problem? Feel free to ask any questions! 

EDIT: Forgot to mention that this problem only occurs on ssid's with EAP, not wlans that are open or use PSK.

[balaji.bandi]

Do you have coverage between building when the Client Roaming ? what is the distance between Building to Building ?

[Denniz]

There is only one building, but yes, there is coverage.

[Flavio Miranda]

Hi

 It can be so many things.

Coverage.  Do you have a site survey indicating that there are overlap between AP cells?

Client issue:    Clients are intitled to take the initiative on the roaming process, the network is passive on it.  Make sure the driver you is up to date.

Authentication:  Which authentication do you use?

 Does the APs are in local mode or  flexconnect

Do you have any feature related to roaming enable on the WLAN?  BSS transition, 11k

[Denniz]

There are some ap's that overlap, but the problem occurs even if the ap's don't overlap. 

Auth; I use EAP on the main SSID, the roaming problem occurs there, but i also have some ssid's that are either open or use PSK, roaming works fine on those networks.

As i use a vWLC the ap's is in flexconnect, you cannot use ap's in local mode on a vWLC.

Yes, i have 11k

[Flavio Miranda]

"There are some ap's that overlap, but the problem occurs even if the ap's don't overlap. "

I might not be clear. The AP cell must overlad in order roaming to occour. I am not saying AP on the same channel, I am saying the AP coverage. You can see this by doing a site survey.

"Auth; I use EAP on the main SSID, the roaming problem occurs there, but i also have some ssid's that are either open or use PSK, roaming works fine on those networks."

  This is interesting. When you use 802.1x you see problems on the roaming but not when you use different auth method.

"As i use a vWLC the ap's is in flexconnect, you cannot use ap's in local mode on a vWLC."

 Yeah, but does support flexconnect with Central switching which is very similar to local mode.

"Yes, i have 11k"

   I suggest test without the 11k. Those feature helps some times and not other times.

But, put the AP in a flexconnect group, if not yet.

"

FlexConnect Groups and Fast Secure Roaming

Fast secure roaming among FlexConnect APs is supported only if the APs are in non-default FlexConnect groups. For OKC, fast roaming is supported between APs in different FlexConnect groups (because key caching is handled by the controller). For 802.11r and CCKM, fast roaming is supported only among APs in the same FlexConnect group. Sticky key caching is not supported with FlexConnect APs."

 You can also test with 802.11v (BSS Transition) and see if improve the roaming capability.

[Denniz]

I actually meant that the ap cells are overlaping

I am using flexconnect local switching.

The ap's were in the default flexconnect group but now i have changed that, the problem still occurs.

[Flavio Miranda]

 Take a look on this link. Maybe this can help you. And start looking on the clients also, this can be a client problem and not the network problem.

https://community.cisco.com/t5/wireless-mobility-knowledge-base/how-to-debug-client-roaming-the-deep-dive/ta-p/3137412

[JPavonM]

Do all APs belong to the same AP Group and Flex Group? Credentials are only cached between APs belonging to the same group so if an AP is not part of it, the client will reconnect.

[Denniz]

Yes, all APs are in the same Flex group and in the same AP group.

[Denniz · Accepted solution]

@Flavio Miranda @JPavonM 

I have solved the issue. The solution for me was actually to turn OFF 802.11r Fast Transition!