DHCP address not being picked up

control · January 2013

I'm very new to Cisco Wireless and have NO experience with it in the wild....

Infrastructure, APs and Controller all in place.

The goal is to have SSID Interent (VLAN 35) for Internet access only.

The AP is connected to a switch and the SSID can be seen ok.

I have a DSL router also connected to the switch with the port in VLAN 35. I was hoping that once a wireless client connects to SSID "Internet" and authenticates, it should then pick up a DHCP address from the DSL router as it would be part of the same VLAN (35), but doesn't seem to work. The Wireless clients are picking up an address from the native data vlan.
At what point does the Wireless client become part of VLAN35?

Is the above even possible? Basically I want the WLAN clients to connect to the SSID Interenet, join vlan 35 and in turn have the DHCP assigned by the DSL router (which is alll configured with scope etc..)

Thanks

SteveO86 · January 2013

I will assume the LAP is operating in local mode and is connected the WLC. Is the port connecting the WLC a trunk and is the SSID tagged with the correct VLAN ID? With a controller and lightwieght deployment all traffic is funneled through the controller so logically the clients are connected to WLC. (When the LAPs are configured for local mode.

control · January 2013

Hi Steve,

The LAP is in flexconnect mode I believe. Not sure if this is relevant to the LAP mode, but we also have a "staff" SSID which picks up internal addresses from our DHCP Server on the LAN. This seems to work ok.
The "internet" SSID on each of the site APs has been tagged with VLAN (35).
The controller resides in a different site, but all our APs a various sites are managed through this controller. We have other sites working ok, although this is the first one tried with using a DSL router for Internet connection.
At what point does a client become part of the VLAN that the SSID is tagged with? From the outcome of the current testing, it's as if the Wireless clients are not becoming part of VLAN35. If they were, and were unable to pick up an IP from the DSL router, I'd expect them to have 169.x.x.x address? What seems to happen is the clients authenticate to the "internet" SSID(tagged with VLAN 35) but request an IP address from the LAN VLAN (2).

SteveO86 · January 2013

FlexConnect is different than local. Mode.

I'd verify the tagging on the SSID. Does this VLAN work properly if you connect directly to network using a wire?

control · January 2013

I'll get this tested and come back with the findings.

So what actually happens once a client authenticates to an SSID? Does the client become part of the relevant tagged VLAN straight away, or at what point does the client join the VLAN? Once a client authenticates, what part does the WLC play when the client is requesting webpages?

I guess if I had a basic understanding on the role of the AP / WLC and what happens during and after authentication I'd be in a better position. Just sort of been thrown into this in a live environment.

DHCP address not being picked up

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