Cisco Catalyst 9800 Series Wireless Controller Software Configuration Guide, Cisco IOS XE 26.1.x

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Cisco Catalyst 9800 Series Wireless Controller Software Configuration Guide, Cisco IOS XE 26.1.x

Restrictions for wireless broadcast, non-IP multicast and multicast VLAN

Updated: April 10, 2026

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Outlines restrictions for wireless broadcast, non-IP multicast, and multicast VLAN, including limitations on VLAN groups, VLAN pool mappings, and forwarding of non-IPv4 multicast and broadcast traffic.

Restrictions

  • Wireless broadcast does not support VLAN groups.

  • If you map a VLAN pool to a WLAN profile, you cannot forward non-IPv4 multicast or broadcast traffic.

  • Non-IPv4 multicasts and broadcasts are only available to clients on the VLAN you mapped to the WLAN. You cannot forward them on VLANs defined by AAA override.

Configure non-IP wireless multicast (CLI)

Enable non-IP multicast traffic on wireless VLANs using commands.

Before you begin

  • The non-IP Multicast feature is disabled globally by default.

  • To allow traffic to pass for non-IP multicast, you must enable global wireless multicast.

  • This feature is not supported in Fabric or Flex deployments.

Procedure

1.

Enable non-IP multicast in all the VLANs.

Example:

Device(config)# wireless multicast non-ip

By default, the non-IP multicast in all the VLANs is in disabled state. You must enable wireless multicast for traffic to pass. Use the no form of this command to disable non-IP multicast in all the VLANs.
2.

Enable non-IP multicast per VLAN.

Example:

Device(config)# wireless multicast non-ip vlan 5

By default, non-IP multicast per VLAN is disabled. Both wireless multicast and wireless multicast non-IP must be enabled to allow traffic to pass. Use the no form of this command to disable non-IP multicast per VLAN.
3.

Exit the configuration mode.

Example:

Device(config)# end

Configure wireless broadcast (GUI)

Enable broadcast packets for wireless clients on selected VLANs using the GUI.

Procedure

1.

Choose Configuration > Services > Multicast.
2.

On the Multicast page, enable Wireless Broadcast to allow packet transmission for wireless clients.

The default value is disabled.
3.

In the Disabled VLAN table, click the arrow next to the VLAN ID to change its status from Disabled to Enabled. This enables broadcast packets for the selected VLAN.

The default value is disabled.
4.

Save the configuration.

Configure wireless broadcast (CLI)

Enable wireless clients to receive specific broadcast packets on the network using commands.

Before you begin

  • This feature applies only to non-ARP and DHCP broadcast packets.

  • By default, the feature is disabled globally.

  • The feature is not supported in Fabric or FlexConnect deployments.

Procedure

1.

Enable broadcast packets for wireless clients.

Example:

Device(config)# wireless broadcast

By default, broadcast packets for wireless clients are disabled. When wireless broadcast is enabled, broadcast traffic is allowed for each VLAN. Use the no form of this command to disable broadcasting packets.
2.

Enable broadcast packets for single VLAN.

Example:

Device(config)# wireless broadcast vlan 3

By default, the Broadcast Packets for a Single VLAN feature is disabled. You must enable wireless broadcast to allow broadcasting. Use the no form of this command to disable broadcast traffic for each VLAN.
3.

Exit the configuration mode.

Example:

Device(config)# end

Configure multicast-over-multicast for AP multicast groups (CLI)

Enable multicast-over-multicast to optimize client multicast traffic distribution across APs using commands.

Procedure

1.

Configure an all-AP multicast group to send a single packet to all the APs.

Example:

Device(config)# ap capwap multicast 239.4.4.4
2.

Enable multicast-over-multicast for multicasting client multicast group traffic to all the APs through the underlying all-AP multicast group.

Example:

Device(config)# wireless multicast 239.4.4.4

IP address : Multicast-over-multicast IP address.
3.

Exit the configuration mode.

Example:

Device(config)# end

Verify wireless multicast

  • The table provides a comprehensive list of commands for verifying various aspects of wireless multicast, including its general status, IP multicast mode, and mDNS bridging state.

Command Description
show wireless multicast Displays the multicast status and IP multicast mode, and each VLAN's broadcast and non-IP multicast status. Also displays the Multicast Domain Name System (mDNS) bridging state.
show wireless multicast group summary Displays all (Group and VLAN) lists and the corresponding MGID values.
show wireless multicast [ sourcesource] groupgroupvlanvlanid Displays details of the specified (S,G,V) and shows all the clients associated with and their MC2UC status.
show ip igmp snooping wireless mcast-spi-count

Displays statistics of the number of multicast SPIs per MGID sent between IOS and the Wireless Controller Module. feature-id []

Displays statistics of the number of multicast SPIs per MGID sent internally between IOS and the Wireless Controller Module. feature-id []
show ip igmp snooping wireless mcast-ipc-count Displays the number of multicast IPCs per MGID sent to the wireless controller module.
show ip igmp snooping wireless mgid Displays the MGID mappings.
show ip igmp snooping igmpv2-tracking Displays the client-to-SGV mappings and the SGV-to-client mappings.
show ip igmp snooping querier vlanvlanid Displays the IGMP querier information for the specified VLAN.
show ip igmp snooping querier detail Displays the detailed IGMP querier information of all the VLANs.
show ipv6 mld snooping querier vlanvlanid Displays the MLD querier information for the specified VLAN.
show ipv6 mld snooping wireless mgid Displays MGIDs for the IPv6 multicast group.

Multicast optimization

Previously, multicast was based on a combination of multicast addresses and VLANs, grouped together as a single entity called MGID. Using the VLAN group can lead to an increase in duplicate packets. When the VLAN group feature is enabled, each client listens to the multicast stream on a different VLAN. As a result, the device creates a separate MGID for each multicast address and VLAN. Consequently, the upstream router sends one copy per VLAN, resulting in a number of copies equal to the number of VLANs in the group. Since all clients use the same WLAN, multiple copies of the multicast packet are sent across the wireless network. The multicast optimization feature suppresses duplication of multicast streams on the wireless medium between the device and the APs.

  • This feature enables you to create a multicast VLAN for multicast traffic. You can configure one of the VLANs in the device as a multicast VLAN, where multicast groups are registered. Clients can listen to a multicast stream on the multicast VLAN. The MGID is generated based on the multicast VLAN and multicast IP addresses.

  • If multiple clients on different VLANs within the same WLAN listen to a single multicast IP address, the device generates a single MGID. The device ensures that all multicast streams from clients in the VLAN group are sent via the multicast VLAN. This approach allows the upstream router to use a single entry for all VLANs in the VLAN group. Only one multicast stream is sent to the VLAN group, even when clients are on different VLANs. As a result, the device sends only one multicast stream over the network.

Configure IP multicast VLAN for WLAN (GUI)

Configure an IP multicast VLAN for a Wireless LAN to enable efficient multicast traffic delivery using the GUI.

Procedure

1.

Choose Configuration > Tags & Profiles > Policy.
2.

Click Add.
3.

In the General tab, enter the Name and Description.
4.

Enable the Central Switching and Central Association toggle buttons.
5.

In the Access Policies tab, under the VLAN settings, choose the vlans from the VLAN/VLAN Group drop-down list and enter the Multicast VLAN.
6.

Click Apply to Device.

Configure IP multicast VLAN for WLAN (CLI)

Set up IP multicast VLAN for WLAN to enable both IPv4 and IPv6 multicast forwarding to APs using commands.

Before you begin

  • This feature is not supported in Fabric or FlexConnect deployments.

  • Multicast VLAN is used for both IPv4 and IPv6 multicast forwarding to APs.

Procedure

1.

Enter the global configuration mode.

Example:

Device# configure terminal
2.

Configure WLAN policy profile and enter the wireless policy configuration mode.

Example:

Device(config)# wireless profile policy default-policy-profile
3.

Configure central association for locally switched clients.

Example:

Device(config-wireless-policy)# central association
4.

Configure WLAN for central switching.

Example:

Device(config-wireless-policy)# central switching
5.

(Optional) Add a description for the policy profile.

Example:

Device(config-wireless-policy)# description test
6.

Assign the profile policy to the VLAN.

Example:

Device(config-wireless-policy)# vlan 32
7.

Configure multicast for the VLAN.

Example:

Device(config-wireless-policy)# multicast vlan 84
8.

Enable the profile policy.

Example:

Device(config-wireless-policy)# no shutdown