When going through a WLC's initial startup wizard, if untagged for the Management Interface’s vlan is desired, enter '0' (zero) when prompted for the management interface's vlan, as this is equivalent to 'untagged':
Most Cisco Access Points are available with two part numbers.
LAPxxx = shipped new from manufacturing with lightweight image
APxxx = shipped new from manufacturing with autonomous image
Same physical hardware.
Same physical ap's, the first is shipped with a lightweight image, the second with an IOS image:
Most AP's can be converted between both modes.
Wireless LAN Controller DHCP Handling
Wireless LAN Controllers perform DHCP proxy' by default. The DHCP Server’ IP Address configured on controller interfaces acts the same way as an 'ip helper' statement on a Cisco router.
With this configuration in place, an IP Helper statement on the wireless clients’ default gateway router is not necessary.
DHCP Proxy can be configured via the WLC’s GUI in 6.x and 7.x code (Controller -> Advanced -> DHCP).
Earlier code requires CLI access for configuration:
(WLC) >show dhcp proxy
DHCP Proxy Behaviour: enabled
(WLC) >config dhcp proxy disable
(WLC) >show dhcp proxy
DHCP Proxy Behaviour: disabled
Lightweight AP modes: Local vs H-Reap
Local mode Access Point: tunnels all traffic to controller, controller responsible for tagging packets and putting them on the wired network, AP's switchport configured in access mode/non trunk.
H-Reap mode Access Point: ap's function similarly to standalone ap's, tag their own traffic, AP's switchport configured as trunk. Vlan tagging requires configuration on each H-Reap mode AP (Via the controller’s Gui).
Legacy Access Points End of Support
1500 Series, LAP-1505, LAP-1510: Last supported in 4.2.M controller code.
1000 Series, AP1010, AP1020, AP1030: Last supported in 4.2 controller code.
These Access Points will not join a controller running code later than supported.
AP console settings
•8 data bits
•1 stop bit
*********No hardware flow control******
These are the same settings for other Cisco devices. It is essential that AP's console session have flow control disabled. Most other Cisco devices will tolerate this setting if not disabled, but AP's will not. The result is typically no display and/or keyboard response.
WLC Dynamic Interfaces, Does it Route?
Those familiar with Cisco routing and switching may get the impression that Wireless LAN Controllers have routing capability. This may seem apparent due to the fact that multiple dynamic interfaces with ip addresses may be configured. WLC's do not route.
The ip addresses assigned to the dynamic interfaces are not used for client traffic passing through the controller.
Dynamic interfaces' IP addresses most useful function is to verify trunk tagging functionality.
For example, we've added a vlan 10 routed SVI on the connected L3 switch. The WLC is directly connected to the L3 switch, and the relevant port is configured to trunk.
Once we've added a WLC dynamic interface mapped to vlan 10, with a correct ip address, we should be able to ping it from the L3 switch. If not, ensure that vlan 10 is forwarding on the switch’s trunk port.
Another use for the dynamic interface IP address is for use with multicast. For wireless multicast receivers connected to local mode ap's, the controller will proxy/spoof IGMP reports to the wired network using the client's corresponding dynamic interface IP address.
By default, multicast traffic is not forwarded by Wireless LAN Controllers for local mode AP's.
A common source of confusion is that Autonomous Mode AP's will forward multicast just as they would unicast, so no configuration is required. In the instance of Autonomous AP's being converted to Controller Based/Lightweight, multicast will no longer work until configured on the controller.
Since Controller based H-Reap mode ap's forward their own traffic, multicast will behave as if the AP were a standalone AP, and no controller configuration is required.
Anchored Wlans. Where does authentication occur?
For Layer 3 authentication, e.g. Web Auth, authentication handling occurs on the Anchor Controller.
For Layer 2 authentication, e.g. 802.1x, authentication handling occurs on the Foreign controller.