Specifications

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Cisco MWR 2941 Mobile Wireless Edge Router Software Configuration Guide, Release 12.2(33)MRB
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Chapter 4 Configuring the Cisco MWR 2941 Router Using the CLI
Configuration Sequence
Step 4 Use the ip igmp ssm-map query dns command to enable DNS-based SSM mapping. By default, the ip
igmp ssm-map command enables DNS-based SSM mapping.
Router(config)# ip igmp ssm-map query dns
Step 5 Use the ip domain multicast command to specify the domain prefix used for DNS-based SSM mapping.
The Cisco IOS software uses the ip-addr.arpa domain prefix by default.
Router(config)# ip domain multicast ssm-map.cisco.com
Step 6 Use the ip name-server command to specify the address of one or more name servers to use for name
and address resolution.
Router(config)# ip name-server 10.48.81.21
Repeat this step to configure additional DNS servers for redundancy, if required.
Configuring Static Traffic Forwarding with SSM Mapping
You can use static traffic forwarding in conjunction with SSM mapping to statically forward SSM traffic
for certain groups. When static traffic forwarding with SSM mapping is configured, the last hop router
uses DNS-based SSM mapping to determine the sources associated with a group. The resulting (S, G)
channels are then statically forwarded.
Follow these steps to configure static traffic forwarding with SSM mapping.
Step 1 Enter enable mode.
Router> enable
Step 2 Enter configuration mode.
Router# configure terminal
Router(config)#
Step 3 Use the interface command to specify the interface on which to statically forward traffic for a multicast
group using SSM mapping and enter interface configuration mode.
Router(config)# interface Vlan600
Router(config-if)#
Step 4 Use the ip igmp static-group command to configure SSM mapping to be used to statically forward a (S,
G) channel out of the interface. Use this command if you want to statically forward SSM traffic for
certain groups, but you want to use DNS-based SSM mapping to determine the source addresses of the
channels.
Router(config-if)# ip igmp static-group 232.1.2.1 source ssm-map
To verify your IP Multicast configuration, see Verifying a Multicast Configuration. For more
information about configuring Multicast, see the Cisco IOS IP Multicast Configuration Guide, Release
12.2SR.
Note The Cisco MWR 2941 does not support all of the commands described in the Cisco IOS Release 12.2SR
documentation.