Примечания к выпуску для Cisco Cisco 4402 Wireless LAN Controller
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Release Notes for Cisco Wireless LAN Controllers and Lightweight Access Points for Release 4.0.179.8
OL-11101-01
Important Notes
Preventing Clients from Accessing the Management Network on a Controller
To prevent or block a wired or wireless client from accessing the management network on a controller
(from the wireless client dynamic interface or VLAN), the network administrator should ensure that
there is no route through which to reach the controller from the dynamic interface or use a firewall
between the client dynamic interface and the management network.
(from the wireless client dynamic interface or VLAN), the network administrator should ensure that
there is no route through which to reach the controller from the dynamic interface or use a firewall
between the client dynamic interface and the management network.
Voice Wireless LAN Configuration
Cisco recommends that load balancing always be turned off in any wireless network that is supporting
voice, regardless of vendor. When load balancing is turned on, voice clients can hear an audible artifact
when roaming, and the handset is refused at its first reassociation attempt.
voice, regardless of vendor. When load balancing is turned on, voice clients can hear an audible artifact
when roaming, and the handset is refused at its first reassociation attempt.
Inter-Subnet Roaming
Currently, multicast traffic cannot be passed during inter-subnet roaming.
Operating Mesh Networks through Switches and Routers
In mesh networks that operate through switches and routers, network round-trip delays between access
points and the controller must be less than 100 milliseconds (ms); otherwise, timing problems may occur
during wireless client authentication. Also, network path outages of 7 seconds or longer between access
points and the controller may cause the access points to lose connectivity.
points and the controller must be less than 100 milliseconds (ms); otherwise, timing problems may occur
during wireless client authentication. Also, network path outages of 7 seconds or longer between access
points and the controller may cause the access points to lose connectivity.
Cisco 7920 Wireless IP Phone Support
When using Cisco 7920 Wireless IP Phones with controllers, make sure that the phones and controllers
are configured as follows:
are configured as follows:
•
Aggressive load balancing must be disabled on a per-controller basis. Otherwise, the initial roam
attempt by the phone may fail, causing a disruption in the audio path.
attempt by the phone may fail, causing a disruption in the audio path.
•
The QoS Basis Service Set (QBSS) information element (IE) must be enabled. The QBSS IE enables
the access points to communicate their channel usage to wireless devices. Because access points
with high channel usage might not be able to handle real-time traffic effectively, the 7920 phone uses
the QBSS value to determine if they should associate with another access point. Use the following
instructions to enable the QBSS IE:
the access points to communicate their channel usage to wireless devices. Because access points
with high channel usage might not be able to handle real-time traffic effectively, the 7920 phone uses
the QBSS value to determine if they should associate with another access point. Use the following
instructions to enable the QBSS IE:
–
sh wlan summary
Note
Use this command to determine the WLAN ID number of the WLAN to which you want
to add QBSS support.
to add QBSS support.
–
config wlan disable wlan_id_number
–
config wlan 7920-support ap-cac-limit enable wlan_id_number
–
config wlan enable wlan_id_number