Enabling Multicast Mode; Configuring Client Roaming - Cisco SD2008T-NA Configuration Manual

Chapter 4 Configuring Controller SettingsWireless Device Access
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Enabling Multicast Mode

Multicasting is disabled by default. Use the commands in
controller CLI.
Table 4-2
Command
config network multicast global
{enable | disable}
config network multicast mode unicast
config network multicast mode multicast
multicast-group-ip-address
You can also enable multicast mode on the Configure > Switch IP System General page on the WCS
interface.

Configuring Client Roaming

The Cisco UWN Solution supports seamless client roaming across lightweight access points managed
by the same controller, between controllers in the same mobility group on the same subnet, and across
controllers in the same mobility group on different subnets.
In controller software release 4.0.206.0 and later, client roaming with multicast is supported.
Note
Ol-9141-03
When you enable multicast mode on the controller you also must configure an LWAPP multicast
group address on the controller. Access points subscribe to the LWAPP multicast group using IGMP.
Cisco 1100, 1130, 1200, 1230, and 1240 access points use IGMP versions 1, 2, and 3. However,
Cisco 1000 series access points use only IGMP v1 to join the multicast group.
Multicast mode works only in Layer 3 LWAPP mode.
Access points in monitor mode, sniffer mode, or rogue detector mode do not join the LWAPP
multicast group address.
When using Multiple controllers on the network, make sure that the same multicast address is
configured on all the controllers.
Multicast mode does not work across intersubnet mobility events such as guest tunneling,
site-specific VLANs, or interface override using RADIUS. However, multicast mode does work in
these subnet mobility events when you disable the Layer 2 IGMP snooping/CGMP features on the
wired LAN.
The controller drops any multicast packets sent to the UDP port numbers 12222, 12223, and 12224.
Make sure the multicast applications on your network do not use those port numbers.
Multicast traffic is transmitted at 6 Mbps in an 802.11a network. Therefore, if several WLANs
attempt to transmit at 1.5 Mbps, packet loss occurs, which breaks the multicast session.
CLI Commands for Configuring Multicast Mode
Table 4-2 to configure multicast mode on the
Multicast Mode
Enable or disable multicasting
Configure the controller to use the unicast method
to send multicast packets
Configure the controller to use the multicast
method to send multicast packets to an LWAPP
multicast group.
Cisco Wireless LAN Controller Configuration Guide
Configuring Client Roaming
4-17