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Catalyst 3750 Switch Software Configuration Guide
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Chapter 36 Configuring IP Multicast Routing
Configuring Advanced DVMRP Interoperability Features
To prevent the default route advertisement, use the no ip dvmrp default-information interface
configuration command.
Responding to mrinfo Requests
The software answers mrinfo requests sent by mrouted systems and Cisco routers and multilayer
switches. The software returns information about neighbors through DVMRP tunnels and all the routed
interfaces. This information includes the metric (always set to 1), the configured TTL threshold, the
status of the interface, and various flags. You can also use the mrinfo privileged EXEC command to
query the router or switch itself, as in this example:
Switch# mrinfo
171.69.214.27 (mm1-7kd.cisco.com) [version cisco 11.1] [flags: PMS]:
171.69.214.27 -> 171.69.214.26 (mm1-r7kb.cisco.com) [1/0/pim/querier]
171.69.214.27 -> 171.69.214.25 (mm1-45a.cisco.com) [1/0/pim/querier]
171.69.214.33 -> 171.69.214.34 (mm1-45c.cisco.com) [1/0/pim]
171.69.214.137 -> 0.0.0.0 [1/0/pim/querier/down/leaf]
171.69.214.203 -> 0.0.0.0 [1/0/pim/querier/down/leaf]
171.69.214.18 -> 171.69.214.20 (mm1-45e.cisco.com) [1/0/pim]
171.69.214.18 -> 171.69.214.19 (mm1-45c.cisco.com) [1/0/pim]
171.69.214.18 -> 171.69.214.17 (mm1-45a.cisco.com) [1/0/pim]
Configuring Advanced DVMRP Interoperability Features
Cisco routers and multilayer switches run PIM to forward multicast packets to receivers and receive
multicast packets from senders. It is also possible to propagate DVMRP routes into and through a PIM
cloud. PIM uses this information; however, Cisco routers and multilayer switches do not implement
DVMRP to forward multicast packets.
These sections describe how to perform advanced optional configuration tasks on your switch to
interoperate with DVMRP devices:
• Enabling DVMRP Unicast Routing, page 36-43 (optional)
• Rejecting a DVMRP Nonpruning Neighbor, page 36-43 (optional)
• Controlling Route Exchanges, page 36-46 (optional)
For information on basic DVMRP features, see the “Configuring Basic DVMRP Interoperability
Features” section on page 36-37.
Step 4
end Return to privileged EXEC mode.
Step 5
show running-config Verify your entries.
Step 6
copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose