layer 2 connectivity

[vishalpatil86]

Hi,

We have following setup -

WLC and AP are in vlan 4001.

When I type sh mac add table command in core switch, i am able to get client's mac learning thru gig5/5.

But when i try to get it from edge switch, i cannot see mac of client. I can see mac of AP learning thru vlan 4001.

My question is how come edge switch is not learning mac of client?

sh mac address table command from core switch -

core#sh mac address-table int gig5/5

Unicast Entries

vlan   mac address     type        protocols               port

-------+---------------+--------+---------------------+--------------------

4001   001b.9e3b.a049   dynamic ip                    GigabitEthernet5/5

highlited is mac of client.

But this entry i cant see in edge switch even if client is conneted trhu this.

pls help on this. I am confused.

[fgasimzade]

Are you sure there is communication between wireless clients and some other people connected to the edge switch?

Also check mac address aging time by issuing command

sh mac address-table aging-time

[fgasimzade]

What is default gateway for wireless clients? Which device is it?

[vishalpatil86]

hi,

there is no communication between

wireless clients and some other people connected to the edge switch.

WLC(service port IP which is 10.5.5.1) is the default gateway for wireless clients.

[fgasimzade]

Well, if there are no packets going between wireless clients and edge switch clients, no wireless clients mac address will be associated with any of the edge switch ports. There has to be any packet with the source mac address of the wireless client to arrive to edge switch trunk port in order to associate this mac with the trunk port.

[vishalpatil86]

yes, but wireless clients talk to wlc thru following path -

client------>AP----->edge switch-------->core switch---------->WLC.

according to my knowledge, there must be mac entry in edge switch for wireless client.

[fgasimzade]

No, AP talks to WLC through LWAPP tunnel, which is set up directly between WLC and AP

[vishalpatil86]

hi,

can you explain this concept in detail?

I dont have any idea about lwapp tunneling

[fgasimzade]

I think this will give a basic knowledge of LWAPP

http://www.cisco.com/en/US/tech/tk722/tk809/technologies_white_paper09186a0080901caa.shtml

[fgasimzade]

This one is much better link

http://my.safaribooksonline.com/book/certification/ccna/9781587058455/controller-discovery-and-association/ch11lev1sec2

[fgasimzade]

http://www.cisco.biz/en/US/products/hw/wireless/ps430/products_qanda_item09186a00806a4da3.shtml

LWAPP FAQ

[naveed817 · Accepted solution]

Hi Vishal,

There's always a tunnel between AP and Controller, and clients traffic go directly to the controller through this tunnel. And from WLC it goes to network. So actually its transparent on the network upto controller. That's the reason you cannot see this on the edge switch.

one more logic for this, when you are using multiple SSID's and vlan's. The ports connect to AP are always access port (single vlan) and port connected to controller are trunk port. Where wireless client are associate with different SSID's. But still they able to communicate over the network. So actually they have a tunnel upto controller.

Thanks

Naveed Shahzad

[vishalpatil86]

thank you naveedv and fgasimzade.

i really appreciate your help