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Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide
78-5897-01
Chapter4 Troubleshooting the System
Troubleshooting Using Cable Flap Lists
Customize Other Flap List Values and Related Commands
The following displays flap list with different sorting options:
show cable modem flap-list[cable <n> | sort-flap | sort-time | sort-interface]
The following sets the threshold value for link establishment:
[no]cable flap-list insertion-time <sec>
Note Amodem is tagged as flapping if the insertion time exceeds this value. Its value can be set
from 60 to 86400 seconds with a default of 180 seconds.
The following sets the number of consecutive missed station maintenance(RNG-RSP) messages that
mustbe missed for a ‘flap’ event to occur. Valueranges from 1-12 with a default of 6 seconds. The hits
and miss counters are not affected:
[no]cable flap-list miss-threshold <miss-threshold>
The followingclears the counters for a cable modem (or all cable modems) in the station maintenance
list:
clear cable modem{ <mac-addr> | <ip-addr> | all } counters
The following displays the QoS, modem status, In and Out octets, IP and MAC addresses per SID:
show int cableslot/port sid
The followingdrops the modem's RF link by removing a modem from the keep-alive polling list. This
forces the modem to reset:
clear cable-modem{ <mac-addr> | <ip-addr> | all } reset
The following uses a MAC layer ping to determine if the cable modem is online. It uses smaller data
unitson the wire than a standard IP ping, resulting in lower overhead. Works even if the IP layer in the
modem is down or hasn’t completed registration:
ping DOCSIS cable-modem<mac-addr | IP address >
The following displays the timing offset, receive power, and QoS values by cable interface, SID, and
MAC address:
show cable modem [<ip-address> | <MAC-address>]
The following displays the current allocation table and frequency assignments:
show cable spectrum-group[spectrum group number]
The following displays maximum, average, and minimum% online time and offline times for a given
SID on a given Cisco uBR7200 interface:
show intslot/port sid connectivity
The following displays input and output rates, input errors, CRC, frames, overruns, underruns,
collisions, interface resets. High input errors in the CMTS retrieved from this query suggests noisy
upstream. In older versions of the chassis, loose midplane and line card screws caused a similar
problem:
show interfaceslot/downstream-port