3-35
Cisco Wireless LAN Controller Configuration Guide
OL-17037-01
Chapter 3 Configuring Ports and Interfaces
Configuring a 4400 Series Controller to Support More Than 48 Access Points
Follow the instructions on the page indicated for the method you want to use.
The following factors should help you decide which method to use if your controller is set for Layer 3
operation:
•
With link aggregation, all of the controller ports need to connect to the same neighbor switch. If the
neighbor switch goes down, the controller loses connectivity.
•
With multiple AP-manager interfaces, you can connect your ports to different neighbor devices. If
one of the neighbor switches goes down, the controller still has connectivity. However, using
multiple AP-manager interfaces presents certain challenges (as discussed in the
section below) when port redundancy is a concern.
Using Link Aggregation
See the
“Enabling Link Aggregation” section on page 3-29
for more information and instructions on
enabling link aggregation.
Note
Link aggregation is the only method that can be used for the Cisco WiSM and Catalyst 3750G Integrated
Wireless LAN Controller Switch controllers.
Using Multiple AP-Manager Interfaces
Note
This method can be used only with Cisco 4400 series stand-alone controllers.
When you create two or more AP-manager interfaces, each one is mapped to a different port (see
). The ports should be configured in sequential order such that AP-manager interface 2 is on
port 2, AP-manager interface 3 is on port 3, and AP-manager interface 4 is on port 4.
Note
AP-manager interfaces need not be on the same VLAN or IP subnet, and they may or may not be on the
same VLAN or IP subnet as the management interface. However, Cisco recommends that you configure
all AP-manager interfaces on the same VLAN or IP subnet.
Note
You must assign an AP-manager interface to each port on the controller.
Before an access point joins a controller, it sends out a discovery request. From the discovery response
that it receives, the access point can tell the number of AP-manager interfaces on the controller and the
number of access points on each AP-manager interface. The access point generally joins the AP-manager
with the least number of access points. In this way, the access point load is dynamically distributed
across the multiple AP-manager interfaces.
Note
Access points may not be distributed completely evenly across all of the AP-manager interfaces, but a
certain level of load balancing occurs.
