How to use CDP to determine if the access point is in Local or FlexConnect Mode

Cisco wireless access points (AP) have a couple different modes of operation when they are used as a light weight access point. FlexConnect (H-Reap) and Local mode. At a high level, the AP in Local mode will build a tunnel to the Wireless LAN Controller (WLC) and send all client data to the controller through that tunnel. An AP in FlexConnect mode buildings the tunnel to the controller for management traffic and will switch the client traffic locally to the switch it’s attached.

AP’s in Local mode require the switch port to be an access port, while a FlexConnect AP should be a trunk port (802.1q) with all of the desired VLANs on it.


While converting an AP to FlexConnect mode, I noticed the difference in the CDP output (see below). In local mode on this Cisco 1131 AP, the remote port (Port on the AP) is “fas 0″ (Fastethernet 0). After converting it to FlexConnect mode, the remote port becomes “fas 0.1″. In this case VLAN 1 is set as the management VLAN.

This is one way that you can use CDP to discover a network’s wireless access points and determine if they are in Local or Flex Connect Mode. This could come in handy when the switch is configured as an access port when it should be a trunk port.

CDP on an a switch connected to an AP in Local Mode

GOAT-SW1#show cdp neighbor
Capability Codes: R – Router, T – Trans Bridge, B – Source Route Bridge
S – Switch, H – Host, I – IGMP, r – Repeater, P – Phone,
D – Remote, C – CVTA, M – Two-port Mac Relay

Device ID Local Intrfce Holdtme Capability Platform Port ID
GOAT-ap3 Fas 0/30 132 T AIR-LAP11 Fas 0
GOAT-ap2 Fas 0/28 133 T AIR-LAP11 Fas 0
GOAT-ap1 Fas 0/27 132 T AIR-LAP11 Fas 0


CDP to a switch connected to an AP in FlexConnect Mode with VLAN’s configured on it.

GOAT-SW1#show cdp neighbor
Capability Codes: R – Router, T – Trans Bridge, B – Source Route Bridge
S – Switch, H – Host, I – IGMP, r – Repeater, P – Phone,
D – Remote, C – CVTA, M – Two-port Mac Relay

Device ID Local Intrfce Holdtme Capability Platform Port ID
GOAT-ap3 Fas 0/30 147 T AIR-LAP11 Fas 0.1
GOAT-ap2 Fas 0/28 125 T AIR-LAP11 Fas 0.1
GOAT-ap1 Fas 0/27 135 T AIR-LAP11 Fas 0.1

***Other models of AP’s may appear a little different***


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About Scape

Over 10 Years in the networking field. Have worked in the Service provider and Enterprise environments. I have worked with Cisco, Foundry/Brocade, F5, Riverbed, Scientific Atlanta, Routers, Switches, Firewalls, Load Balancers, WAN Accelerators, DWDM, SONET, Multicast etc...

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