Cisco Systems 3130 User Manual
44-43
Cisco Catalyst Blade Switch 3130 for Dell Software Configuration Guide
OL-13270-01
Chapter 44 Configuring IP Multicast Routing
Configuring Basic DVMRP Interoperability Features
Configuring a DVMRP Tunnel
The software supports DVMRP tunnels to the MBONE. You can configure a DVMRP tunnel on a router
or multilayer switch if the other end is running DVMRP. The software then sends and receives multicast
packets through the tunnel. This strategy enables a PIM domain to connect to the DVMRP router when
all routers on the path do not support multicast routing. You cannot configure a DVMRP tunnel between
two routers.
or multilayer switch if the other end is running DVMRP. The software then sends and receives multicast
packets through the tunnel. This strategy enables a PIM domain to connect to the DVMRP router when
all routers on the path do not support multicast routing. You cannot configure a DVMRP tunnel between
two routers.
When a Cisco router or multilayer switch runs DVMRP through a tunnel, it advertises sources in
DVMRP report messages, much as it does on real networks. The software also caches DVMRP report
messages it receives and uses them in its RPF calculation. This behavior enables the software to forward
multicast packets received through the tunnel.
DVMRP report messages, much as it does on real networks. The software also caches DVMRP report
messages it receives and uses them in its RPF calculation. This behavior enables the software to forward
multicast packets received through the tunnel.
When you configure a DVMRP tunnel, you should assign an IP address to a tunnel in these cases:
•
To send IP packets through the tunnel
•
To configure the software to perform DVMRP summarization
The software does not advertise subnets through the tunnel if the tunnel has a different network number
from the subnet. In this case, the software advertises only the network number through the tunnel.
from the subnet. In this case, the software advertises only the network number through the tunnel.
Beginning in privileged EXEC mode, follow these steps to configure a DVMRP tunnel. This procedure
is optional.
is optional.
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
access-list access-list-number {deny |
permit} source [source-wildcard]
permit} source [source-wildcard]
Create a standard access list, repeating the command as many times as
necessary.
necessary.
•
For access-list-number, the range is 1 to 99.
•
The deny keyword denies access if the conditions are matched. The
permit keyword permits access if the conditions are matched.
permit keyword permits access if the conditions are matched.
•
For source, enter the number of the network or host from which the
packet is being sent.
packet is being sent.
•
(Optional) For source-wildcard, enter the wildcard bits in dotted
decimal notation to be applied to the source. Place ones in the bit
positions that you want to ignore.
decimal notation to be applied to the source. Place ones in the bit
positions that you want to ignore.
Recall that the access list is always terminated by an implicit deny
statement for everything.
statement for everything.
Step 3
interface tunnel number
Specify a tunnel interface, and enter interface configuration mode.
Step 4
tunnel source ip-address
Specify the source address of the tunnel interface. Enter the IP address
of the interface on the switch.
of the interface on the switch.
Step 5
tunnel destination ip-address
Specify the destination address of the tunnel interface. Enter the IP
address of the mrouted router.
address of the mrouted router.
Step 6
tunnel mode dvmrp
Configure the encapsulation mode for the tunnel to DVMRP.
Step 7
ip address address mask
or
ip unnumbered type number
Assign an IP address to the interface.
or
Configure the interface as unnumbered.
Step 8
ip pim [dense-mode | sparse-mode]
Configure the PIM mode on the interface.