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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter24 Configuring IP Multicast Routing
Configuring Basic DVMRP Interoperability Features
To disable the filter, use the no ip dvmrp accept-filter access-list-number [distance] neighbor-list
access-list-number interface configuration command.
This example shows how to configure a DVMRP tunnel. In this co nfigu rat ion, the IP addr e ss of t he
tunnel on the Cisco multilayer switch is assigned unnumbered, which causes the tunnel to appear to have
the same IP address as Gigabit Ethernet interface 0/1. The tunnel e ndpoint source address is 172.16.2.1,
and the tunnel endpoint address of the remote DVMR P ro ute r to w hic h th e tunne l is co nnec ted
is 192.168.1.10. Any packets sent through the tunnel are encapsulated in an out er IP he ader. The Cisco
multilayer switch is configured to accept incoming DVMRP reports with a distance of 100
from 198.92.37.0 through 198.92.37.255.
Switch(config)# ip multicast-routing
Switch(config)# interface tunnel 0
Switch(config-if)# ip unnumbered gigabitethernet 0/1
Switch(config-if)# ip pim dense-mode
Switch(config-if)# tunnel source gigabitethernet 0/1
Switch(config-if)# tunnel destination 192.168.1.10
Switch(config-if)# tunnel mode dvmrp
Switch(config-if)# ip dvmrp accept-filter 1 100
Switch(config-if)# interface gigabitethernet 0/1
Switch(config-if)# ip address 172.16.2.1 255.255.255.0
Switch(config-if)# ip pim dense-mode
Switch(config)# exit
Switch(config)# access-list 1 permit 198.92.37.0 0.0.0.255
Advertising Network 0.0.0.0 to DVMRP Neighbors
If your multilayer switch is a neighbor of an mrouted v ersi on 3.6 d evic e, you can c onfi gure t he Ci sco
IOS software to advertise network 0.0.0.0 (the default route) to the DVMRP neighbor. The DVMRP
default route computes the RPF information for any multicast sources that do not match a more specific
route.
Do not advertise the DVMRP default into the MBONE.
Beginning in privileged EXEC mode, follow these steps to advertise n etw ork 0 .0 .0.0 to D VM RP
neighbors on an interface:
Step11 show running-config Verify your entries.
Step12 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Enter interface configuration mode, and specify the interface that is
connected to the DVMRP router.