user manual

Configuring Headend Broadband Access Router Features
Configuring the Upstream Cable Interface
MC-558
Cisco IOS Multiservice Applications Configuration Guide
To return the upstream time adjustment ranging value to the default of 2 seconds, enter the following
command in cable interface configuration mode:
CMTS01(config-if)# no cable upstream usport time-adjust continue
To return the upstream time adjustment threshold value to the default of 1 second, enter the following
command in cable interface configuration mode:
CMTS01(config-if)# no cable upstream usport time-adjust threshold
Verifying Upstream Timing Adjustment
To verify whether or not upstream timing adjustment has been configured and activated, enter the show
running-config command and look for the cable interface configuration information. If upstream timing
adjustment is enabled, either or both of the continue and threshold timing adjustment entries will be
displayed in the show running-config output. If both the continue and threshold upstream timing
adjustments have been disabled, no timing adjustment entry will be displayed in the
show running-config output.
Troubleshooting Tips
To troubleshoot the configuration, perform the following tasks:
• Make sure the cable connections are not loose or disconnected.
• Make sure the Cisco cable modem card is firmly seated in its chassis slot and the captive installation
screws are tight.
• Make sure you entered the correct slot and port numbers when you typed the command.
• Make sure you entered the correct upstream port number:
– On the MC16C cable modem card, this can be u0 to u5.
– On the MC14C cable modem card, this can be u0 to u3.
– On the MC12C cable modem card, this can be u0 or u1.
– On the MC11C cable modem card, this can be u0 only.
Activating the Upstream Ports
Each upstream port must be activated to enable upstream data transmission from the cable modems on
the HFC network to the Cisco uBR7200 series router.
Note The upstream cable interface will not operate until you either set a fixed upstream
frequency or create and configure a spectrum group. See the “Setting the Upstream
Frequency” or the “Configuring and Activating Frequency Agility” sections in this chapter
for details.