Reference Manual

Manage Stacking and Redundancy
278
ProSAFE Wireless Controller WC9500
Manage Redundancy for a Single Controller
The wireless controller supports 1:1 redundancy with failover. Redundancy is implemented
through the use of the Virtual Router Redundancy Protocol (VRRP).
For information about N:1 redundancy, see Manage a Redundancy Group with N:1
Redundancy on page 282.
VRRP Redundancy Concepts
You can configure two controllers to form a redundancy group. You then designate one
controller in the redundancy group as the primary controller and the other wireless controller
as the redundant controller. If the primary controller fails or is disconnected from the network,
an automatic failover to the redundant controller occurs. The redundant controller then takes
over all functions of the primary controller.
Note: When a redundancy failover occurs, wireless clients might experience
a service interruption of a few seconds.
Requirements and Restrictions for Redundancy
These are the requirements and restrictions for a single controller with redundancy to
function correctly:
• The primary controller and redundant controller must be in the same management VLAN
and IP subnet.
• The VRRP ID for the relationship between the primary controller and redundant controller
must be unique and also different from any other VRRP IDs that might be used for other
purposes in the network.
• The primary controller and redundant controller must run the same firmware version. If
the firmware versions do not match, redundancy does not work.
• The licenses on the redundant controller must match those on the primary controller. If
the licenses do not match, redundancy does not work.
• The primary controller and redundant controller must be assigned the same controller IP
address at which they provide the service, but each controller is assigned its own unique
local IP address.