000C.64ff.eb95
Cable3/0/U4
3314
55605 50460 0
*42175 47533 Jan 27 02:49:10
Router#
Use an SNMP tool to retrieve the ccsFlapTable and filter it by the decimal MAC address. For example, using
the standard Unix
getone
command, you would give the following command:
csh%
getmany -v2c 192.168.100.121 public ccsFlapTable | grep 0.12.100.255.235.149
ccsFlapUpstreamIfIndex.0.12.100.255.235.149 = 15
ccsFlapDownstreamIfIndex.0.12.100.255.235.149 = 17
ccsFlapInsertionFails.0.12.100.255.235.149 = 3315
ccsFlapHits.0.12.100.255.235.149 = 55608
ccsFlapMisses.0.12.100.255.235.149 = 50460
ccsFlapCrcErrors.0.12.100.255.235.149 = 0
ccsFlapPowerAdjustments.0.12.100.255.235.149 = 42175
ccsFlapTotal.0.12.100.255.235.149 = 47534
ccsFlapLastFlapTime.0.12.100.255.235.149 = 07 d4
01 1b
02 33
1a 00
ccsFlapCreateTime.0.12.100.255.235.149 = 07 d4
01 16
03 23
22 00
ccsFlapRowStatus.0.12.100.255.235.149 = active(1)
ccsFlapInsertionFailNum.0.12.100.255.235.149 = 3315
ccsFlapHitNum.0.12.100.255.235.149 = 55608
ccsFlapMissNum.0.12.100.255.235.149 = 50460
ccsFlapCrcErrorNum.0.12.100.255.235.149 = 0
ccsFlapPowerAdjustmentNum.0.12.100.255.235.149 = 42175
ccsFlapTotalNum.0.12.100.255.235.149 = 47534
ccsFlapResetNow.0.12.100.255.235.149 = false(2)
ccsFlapLastResetTime.0.12.100.255.235.149 = 07 d4
01 16
03 20
18 00
csh%
To request just one particular value, use the decimal MAC address as the instance for that object:
csh%
getone -v2c 172.22.85.7 public ccsFlapMisses.0.12.100.255.235.149
ccsFlapMisses.0.12.100.255.235.149 = 50736
csh %
Troubleshooting Suggestions
This section provides tips on how to interpret the flap-list counters, as well as how to determine the optimum
power level for a flapping cable modem.
Troubleshooting Tips
This section includes suggestions on how to interpret different network conditions based on the flap-list
statistics:
•
Condition 1: Low miss or hit ratio, low insertion, low P-Adj, low flap counter, and old time stamp.
Analysis: This exhibits an optimal network situation.
•
Condition 2: High ratio of misses over hits (> 10 percent). Analysis: Hit and miss analysis should be
done after the Ins count stops incrementing. In general, if the hit and miss counts are about the same
order of magnitude, the upstream can be experiencing noise. If the miss count is greater, then the modem
is probably dropping out frequently and not completing registration. The upstream or downstream might
not be stable enough for reliable link establishment. Very low hits and miss counters and high insertion
counters indicate provisioning problems.
•
Condition 3: Relatively high power-adjustment counter. Analysis: Indicates that the power-adjustment
threshold is probably set at default value of 2 dB. The modem transmitter step size is 1.5 dB, but the
headend can command 0.25 dB step sizes. Tuning your power threshold to 6 dB is recommended to
Cisco cBR Series Converged Broadband Routers Troubleshooting and Network Management Configuration
Guide for Cisco IOS XE Fuji 16.8.x
210
Flap List Troubleshooting
Troubleshooting Suggestions