Cisco Wireless Controller 8.1 clients changing ip address moving from one AP to another.

[Kunal Kapil]

Hi All,

I would appreciate your assistance to understand the existing issue with our wireless infrastructure.

We have Cisco WLC 7500 with 8.1 software image.

 All the AP's are in Flexconnect mode.

Local branch configuration connecting to WAP is as below.

interface GigabitEthernet3/0/5
 description 
 switchport trunk encapsulation dot1q
 switchport trunk native vlan xx
 switchport trunk allowed vlan xx,yy,zz
 switchport mode trunk
end

DHCP server is not local to the branch so we are using helper address.

Cisco documentation says that if client is roaming from 1 AP to another (those are under the same controller) there should be seamless roaming.

Because controller will update the entries in its DB.

But in one of my branch sites , I have moved with my laptop from 1 AP to another and the laptop different IP address  and the roaming is not seamless.

I am not able to understand the reason. Could you please suggest the behavior is normal or there is something wrong in switch or controller config ?

Thanks again for your time to respond.

[Rasika Nayanajith]

But in one of my branch sites , I have moved with my laptop from 1 AP to another and the laptop different IP address  and the roaming is not seamless

First I would check both APs are in same AP group.

Also both those AP configured in same way to terminate given WLAN traffic to same vlan locally. (assuming you are using FlexConenct local switching)

If there is different subnets for those AP/wlan configured, it is expected behaviour as FlexConnect does not support L3 roaming

HTH

Rasika

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[Kunal Kapil]

Thanks for your response Rasika.

I checked that both WAP's are in same group

compared he config of WAP's. They are same.

These clients get Ip from the same subnet there is same vlan for both all the wap's on the floor.

I wonder if they are forced to authenticate again that's why they look for new ip address ?

[Rasika Nayanajith]

Do the same test few times and confirm it is happening every time.

Typically client should keep the same IP in this scenario.

HTH

Rasika