Cisco Systems 3.2 Wireless Office Headset User Manual


 
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Cisco Wireless LAN Controller Configuration Guide
OL-8335-02
Chapter 1 Overview
Wireless LAN Controller Platforms
Enables and/or disables the 802.11a, 802.11b and 802.11g Cisco 1000 series lightweight access
point networks.
Enables or disables Radio Resource Management (RRM).
To use the Startup Wizard, refer to the “Using the Configuration Wizard” section on page 4-2.
Cisco Wireless LAN Controller Memory
The Cisco Wireless LAN Controller contain two kinds of memory: volatile RAM, which holds the
current, active Cisco Wireless LAN Controller configuration, and NVRAM (non-volatile RAM), which
holds the reboot configuration. When you are configuring the operating system in a Cisco Wireless LAN
Controller, you are modifying volatile RAM; you must save the configuration from the volatile RAM to
the NVRAM to ensure that the Cisco Wireless LAN Controller reboots in the current configuration.
Knowing which memory you are modifying is important when you are:
Using the Configuration Wizard
Clearing the Controller Configuration
Saving Configurations
Resetting the Controller
Logging Out of the CLI
Cisco Wireless LAN Controller Failover Protection
Each Cisco Wireless LAN Controller has a defined number of communication ports for Cisco 1000
series lightweight access points. This means that when multiple controllers with unused access point
ports are deployed on the same network, if one controller fails, the dropped access points automatically
poll for unused controller ports and associate with them.
During installation, Cisco recommends that you connect all lightweight access points to a dedicated
controller, and configure each lightweight access point for final operation. This step configures each
lightweight access point for a primary, secondary, and tertiary controller, and allows it to store the
configured WLAN Solution Mobility Group information.
During failover recovery, the configured lightweight access points obtain an IP address from the local
DHCP server (only in Layer 3 Operation), attempt to contact their primary, secondary, and tertiary
controllers, and then attempt to contact the IP addresses of the other controllers in the Mobility group.
This prevents the access points from spending time sending out blind polling messages, resulting in a
faster recovery period.
In multiple-controller deployments, this means that if one controller fails, its dropped access points
reboot and do the following under direction of the Radio Resource Management (RRM):
Obtain an IP address from a local DHCP server (one on the local subnet).
If the Cisco 1000 series lightweight access point has a primary, secondary, and tertiary controller
assigned, it attempts to associate with that controller.
If the access point has no primary, secondary, or tertiary controllers assigned or if its primary,
secondary, or tertiary controllers are unavailable, it attempts to associate with a master controller on
the same subnet.