Configuring Routing
Configuring the Cisco uBR900 Series Cable Access Routers 39
Configuring Routing

DOCSIS-compliant transparent bridging is the factory default configuration of the CiscouBR900

series cable access router. To change the configuration of your cable access router from bridging to

routing using the CLI, perform the following tasks, starting in global configuration mode:

Step Command Purpose
1uBR924(config)#interface cable-modem0 Enter interface configuration mode for the cable access
router interface.
2uBR924(config-if)#no cable-modem compliant bridge
uBR924(config-if)#no bridge-group 59
uBR924(config-if)#end
Turn off DOCSIS-compliant bridging.
Remove the default bridge group assignment from the
cable interface.
Return to global configuration mode.
3uBR924(config)#ip routing
uBR924(config)#ip subnet-zero
uBR924(config)#ip route <IP address of CMTS> <subnet
mask of CMTS>
Enable IP routing for the cable access router.
Enable the use of subnet zero for interface addresses and
routing updates.
Create a static route to the CMTS to make sure that Time
of Day (TOD) packets are properly routed out of the cable
access router.
4uBR924(config)#router rip Enter router configuration mode and enable Routing
Information Protocol (RIP) on the cable access router.
5uBR924(config-router)#network network-number Specify the network connected to the cable access router
on which the RIP process will operate. If the cable access
router is attached to more than one network, enter each IP
address in a separate command.
6uBR924(config-router)#end
uBR924(config)#interface cable-modem0
Exit router configuration mode.
Return to interface configuration mode for the cable
access router interface.
7uBR924(config-if)#ip rip receive v 2 Specify that only RIP Version 2 packets will be received
on the coaxial cable interface.
8uBR924(config-if)#ip rip send v 2 Specify that only RIP Version 2 packets will be sent on
the coaxial cable interface.
9uBR924(config-if)#end
uBR924(config)#interface ethernet0
Exit interface configuration mode for the cable access
router interface and enter interface configuration mode for
the Ethernet0 interface.
10 uBR924(config-if)#no bridge-group 59 Remove the default bridge group assignment from the
Ethernet0 interface.
11 uBR924(config-if)#ip rip receive v 2 Specify that only RIP Version 2 packets will be received
on this Ethernet interface.
12 uBR924(config-if)#ip rip send v 2 Specify that only RIP Version 2 packets will be sent on
this Ethernet interface.
13 uBR924(config-if)#Ctrl-z
uBR924#copy running-config startup-config
Building configuration...
Return to privileged EXEC mode.
Save the configuration to nonvolatile RAM so that it
won’t be lost in the event of a reset, power cycle, or power
outage.