Activate the Downstream Carrier
Configuring Cisco uBR7246 Universal Broadband Router Features VC-143
Troubleshooting Tips
If you are having trouble:
•Make sure the cable connections are not loose or disconnected.
•Make sure the cable modem card is firmly seated in its CiscouBR7246 chassis slot.
•Make sure that you have entered the correct slot and port numbers when you typed the command.
•Make sure the downstream carrier is active by entering the cable downstream if-output
command.
Activate the Downstream Carrier
To activate a downstream port on a cable modem card for digital data transmissions over the HFC
network, use the following commands in global configuration mode:
Validation Tips
To verify that the downstream carrier is active (up), enter the show controllers cable command for
the downstream port that you have just configured:
router# show controllers cable 6/0 downstream
Cable6/0 Downstream is up
Frequency=96000000, Channel Width 6 MHz, 64-QAM, Symbol Rate 5.056941 Msps
FEC ITU-T J.83 Annex B, R/S Interleave I=32, J=4
Troubleshooting Tips
If you are having trouble with this configuration:
•Make sure the cable connections are not loose or disconnected.
•Make sure the cable modem card is firmly seated in its CiscouBR7246 chassis slot.
•Make sure that you have entered the correct slot and port numbers when you typed the command.
Step Command Purpose
1interface cable port/slot Specify a cable interface and enter the cable interface
configuration mode.
2cable downstream if-output Activate downstream digital data from the CiscouBR7246.
(This is the default setting.)