Enabling Link Aggregation - Cisco 2100 Series Configuration Manual

Chapter 3 Configuring Ports and Interfaces
Enter one of these commands to configure the STP port path cost on the STP ports:
Step 4
•
•
Step 5 Enter config spanningtree port priority 0-255 port-number to configure the port priority on STP ports.
The default priority is 128.
If necessary, enter config spanningtree switch bridgepriority 0-65535 to configure the controller's
Step 6
STP bridge priority. The default bridge priority is 32768.
If necessary, enter config spanningtree switch forwarddelay 4-30 to configure the controller's STP
Step 7
forward delay in seconds. The default forward delay is 15 seconds.
If necessary, enter config spanningtree switch hellotime 1-10 to configure the controller's STP hello
Step 8
time in seconds. The default hello time is 2 seconds.
If necessary, enter config spanningtree switch maxage 6-40 to configure the controller's STP maximum
Step 9
age. The default maximum age is 20 seconds.
After you configure STP settings for the ports, enter config spanningtree switch mode enable to enable
Step 10
STP for the controller. The controller automatically detects logical network loops, places redundant
ports on standby, and builds a network with the most efficient pathways.
Enter save config to save your settings.
Step 11
Enter show spanningtree port and show spanningtree switch to verify that your changes have been
Step 12
saved.

Enabling Link Aggregation

Link aggregation (LAG) is a partial implementation of the 802.3ad port aggregation standard. It bundles
all of the controller's distribution system ports into a single 802.3ad port channel, thereby reducing the
number of IP addresses needed to configure the ports on your controller. When LAG is enabled, the system
dynamically manages port redundancy and load balances access points transparently to the user.
Cisco 4400 series controllers support LAG in software release 3.2 and higher, and LAG is enabled
automatically on the controllers within the Cisco WiSM and the Catalyst 3750G Integrated Wireless
LAN Controller Switch. Without LAG, each distribution system port on the controller supports up to 48
access points. With LAG enabled, a 4402 controller's logical port supports up to 50 access points, a 4404
controller's logical port supports up to 100 access points, and the logical port on each Cisco WiSM
controller supports up to 150 access points.
You can bundle all four ports on a 4404 controller (or two on a 4402 controller) into a single link.
Note
Figure 3-11
OL-17037-01
config spanningtree port pathcost 1-65535 {port-number | all}—Specifies a path cost from 1 to
65535 to the port.
config spanningtree port mode pathcost auto {port-number | all}—Enables the STP algorithm to
automatically assign the path cost. This is the default setting.
illustrates LAG.
Cisco Wireless LAN Controller Configuration Guide
Enabling Link Aggregation
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