Cisco Systems uBR7200 Series manual

CHAPTER 4-1 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 4 Troubleshooting the System This chapter contains troubleshooting information. The chapter includes the following sections: • Using a Cable Modem at the Headend to V erify Do wnstream Signals • Managing Cable Modems on the HFC Network • Pollin[...]

4-2 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network Tips The SNR estimate for a cable modem installed at a headend should be between 35 dB and 39 dB. Although the exact v alue displayed will v ary from cable modem to cable modem, va[...]

4-3 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network Verify Sync Message Interval T o verify whether or not a sync message interv al is conf igured, enter the show running-conf ig command and look for the cable interface conf igurati[...]

4-4 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network T o acti v ate cable modem upstream address verif ication, use the following cable interf ace conf iguration command. Verify Cable Modem Upstream Address Verification T o verify wh[...]

4-5 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network Although the binary exponential backof f algorithm operates in a distributed fashion at dif ferent CMs, the CMTS provides centralized control for the backof f algorithm. T o achiev[...]

4-6 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network Caution Only a trained CMTS administrator should adjust these v alues. T o conf igure the dynamic map advance algorithm, use the follo wing command in cable interface conf iguratio[...]

4-7 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network T o conf igure per modem f ilters, use the follo wing commands in cable interf ace conf iguration mode. Caution The system applies f ilters after the cable modem registers with the[...]

4-8 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network Configure the Maximum Number of Hosts Attached to a Cable Modem T o specify the maximum number of hosts that can be attached to a subscriber’ s cable modem, use the following com[...]

4-9 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network Verify Clear Cable Modem Reset T o verify whether or not the clear cable modem reset command has remov ed a cable modem from the station maintenance list and forced it to start a r[...]

4-10 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network Verify Clear Cable Modem Counters T o verify whether or not the counters in the Station Maintenance List are cleared, enter the follo wing command. The station maintenance list co[...]

4-11 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network T o conf igure this, use the following command in cable interface conf iguration mode. Using Cisco IOS Release 12.0(5)T1 or higher , the software supports: • Generic calendar qu[...]

4-12 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network • Using time scheduled spectrum management, the upstream channel frequency reassignment process is initiated at a conf igured time of day or week. W ith combined blind and time [...]

4-13 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network Sample output: noisy1# show cable spec Group Frequency Upstream Weekly Scheduled Power Shared No. Band Port Availability Level Spectrum (Mhz) From Time: To Time: (dBmV) 1 10.000- [...]

4-14 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network Sample output: noisy1# show cable hop Upstream Port Poll Missed Min Missed Hop Hop Corr Uncorr Port Status Rate Poll Poll Poll Thres Period FEC FEC (ms) Count Sample Pcnt Pcnt (se[...]

4-15 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing Cable Modems on the HFC Network noisy1# show cable hop Upstream Port Poll Missed Min Missed Hop Hop Corr Uncorr Port Status Rate Poll Poll Poll Thres Period FEC FEC (ms) Count Sample Pcnt Pcnt (sec) Errors Error[...]

4-16 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Polling Cable Modems Sample output: noisy1# show cable hop Upstream Port Poll Missed Min Missed Hop Hop Corr Uncorr Port Status Rate Poll Poll Poll Thres Period FEC FEC (ms) Count Sample Pcnt Pcnt (sec) Errors Errors Cab[...]

4-17 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Polling Cable Modems Enable SNMP Configure Remote Modem Monitoring Verifying Remote Query Information T o display information from a queried modem, enter the show cable modem r emote-query command. R7732-01-uBR7246# sh c[...]

4-18 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses Monitoring and Maintaining Remote Querying Use the following sho w commands to gather status information about the specif ied modems. Understanding Show Command Responses General Show[...]

4-19 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses • The show cable f lap-list and sho w cable modem commands no w indicate when the Cisco uBR7200 series router has detected an unstable return path for a particular modem and has com[...]

4-20 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses See the sample command output below: router# show cable modem Interface Prim Online Timing Rec QoS CPE IP address MAC address Sid State Offset Power Cable3/0/U0 1 online 2257 0.00 3 0[...]

4-21 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses Note * means the noise po wer adjustment method is acti ve for this modem; ! means the modem has reached its maximum transmit po wer • The QoS column contains the service class assi[...]

4-22 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses See the follo wing sample for detailed output of the show cable modem command: router# show cable modem detail Interface SID MAC address Max CPE Concatenation Rx SNR Cable3/0/U0 1 009[...]

4-23 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses See the following sample output of unre gistered modems connected on upstream channel 0 for cable interface 3, port 0: router# show cable modem cable 3/0 upstream 0 unregistered Inter[...]

4-24 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses Follo wing is a response to the show cable modem maintenance command using Cisco IOS Release 12.0(5)T1: uBR7200# show cable modem maintenance Interface SID MAC Address SM Exhausted SM[...]

4-25 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses T able 4-16 Show Interface Cable Command F ield Descriptions Field Description Cable slot/port is up/...administrati vely do wn Indicates whether the interface hardware is currently a[...]

4-26 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses drops Indicates the number of packets dropped due to a full queue Fiv e minute input rate Fiv e minute output rate A verage number of bits and pack ets transmitted per second in the l[...]

4-27 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses See the following sample output for the do wnstream cable interface of slot 6 on port 0 from the show interface cable downstr eam command: router# show interface cable 6/0 downstream [...]

4-28 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses T able 4-18 Show Interface Cable Upstream Command F ield Descriptions Field Description Cable Indicates the location of the upstream interface Upstream is up/...administrati vely do w[...]

4-29 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses CIR admission control (formerly: Current Admission Control Status) Indicates the status of admission control on the upstream channel ENFORCED status allows users to enable admission c[...]

4-30 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses Enhanced Show Interface Upstream Output The show interface cable upstr eam command is enhanced in Cisco IOS Release 12.0(7)XR2, Cisco IOS Release 12.1(1a)T1, or higher CMTS images to [...]

4-31 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses • Counters for each type of upstream slot scheduled in the MAPs for this upstream channel---The “Init Mtn IEs 800” means that the MA C scheduler has added 800 initial maintenanc[...]

4-32 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses See the follo wing display output for the verbose keyword e xtension for all SIDs on the specif ied interface: router# show interface c3/0 sid counters verbose Sid : 1 Input packets :[...]

4-33 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Understanding Show Command Responses See the following display for the counters of the SIDs connected to the specif ied interface: router# show interface c3/0 sid counters Sid Inpackets Inoctets Outpackets Outoctets Rate[...]

4-34 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Troubleshooting Using Cable Flap Lists Show Cable QoS Profile Follo wing is a response to the show cable qos pr of ile command. The display shows T oS specif ications: uBR7200# show cable qos profile Service Prio Max Gua[...]

4-35 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Troubleshooting Using Cable Flap Lists list keeps track of the cable modem MAC address, up and do wn transitions, re gistration e vents, missed periodic ranging packets, upstream po wer adjustments and the physical inter[...]

4-36 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Troubleshooting Using Cable Flap Lists Tips In Cisco IOS Release 12.0(7)XR2, Cisco IOS Release 12.1(1a)T1, and higher , the system supports automatic po wer adjustments. The show cable f lap-list and show cable modem com[...]

4-37 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Troubleshooting Using Cable Flap Lists Follo wing is a sample response to the show cable f lap command: uBR7200# show cable flap Mac Addr CableIF Ins Hit Miss CRC P-Adj Flap Time 0010.9500.461f C3/0 U1 56 18857 887 0 1 1[...]

4-38 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Troubleshooting Using Cable Flap Lists T able 4-20 Flap List Statistics Description Statistic Description MA C ID This is the MA C-layer address of a cable modem. The f irst six digits indicate the vendor ID of the cable[...]

4-39 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Troubleshooting Using Cable Flap Lists Hit and Miss The HIT and MISS columns are keepaliv e polling statistics between the Cisco uBR7200 series and the cable modem. The station maintenance process occurs for ev ery modem[...]

4-40 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Troubleshooting Using Cable Flap Lists Troubleshoot with the Flap List This section includes suggestions on how to interpret dif ferent network conditions based on the f lap list statistics: • Condition 1: Low miss/hit[...]

4-41 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Troubleshooting Using Cable Flap Lists Set Cable Flap List Aging Y ou can specify the number of days to record and retain f lapping activity on cable modems currently in the f lap-list table. This value is kno wn as the [...]

4-42 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Troubleshooting Using Cable Flap Lists Set Cable Flap List Power Adjustment Threshold Y ou can specify the po wer adjustment threshold that will cause a f lap-list event to be recorded. When the power adjustment of a cab[...]

4-43 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Troubleshooting Using Cable Flap Lists Verify Cable Flap List Miss Threshold T o verify the cable f lap list miss threshold, enter the show cable f lap list command: CMTS01# show cable flap list Mac Addr CableIF Ins Hit [...]

4-44 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Troubleshooting Using Cable Flap Lists Customize Other Flap List Values and Related Commands The follo wing displays f lap list with different sorting options: show cable modem f lap-list [cable <n> | sort-f lap | [...]

4-45 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Performing Amplitude Averaging Performing Amplitude Averaging The Cisco uBR7200 series uses an av eraging algorithm to determine the optimum po wer le vel for a cable modem with lo w carrier-to-noise ratio that is making[...]

4-46 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Performing Amplitude Averaging Note The threshold default is 1 dB. The tolerable v alue default is 2 dB. The po wer adjustment is 30 percent. Caution Default settings are adequate for system operation. Amplitude a veragi[...]

4-47 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Setting Downstream Test Signals The follo wing example sho ws ho w to change the po wer adjustment method when the frequenc y adjustment packet count reaches 50 percent: router(config-if)# cable upstream 0 freq-adj avera[...]

4-48 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Pinging Unresponsive Cable Modems Configure PRBS Test Signals Verify Test Signal Output T o verify the output of a continuous-wave test signal or the output of a PRBS test signal, use a spectrum analyzer on the do wnstre[...]

4-49 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Using Cable Interface Debug Commands Verify the Ping The ping docsis command returns a verif ication from a cable modem that is pinged: Queueing 5 MAC-layer station maintenance intervals, timeout is 25 msec: !!!!! Succes[...]

4-50 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Using Cable Interface Debug Commands Debug Environmental Monitor Messages This command acti vates deb ugging of the Cisco uBR7200 series en vironmental monitor . When this command is acti v ated, all en vironmental monit[...]

4-51 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Using Cable Interface Debug Commands T o deacti v ate debugging of cable MA C messages, use the following command: CMTS01# no debug cable mac-messages Debug Cable Maps This command activ ates debugging of cable maps that[...]

4-52 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Using Cable Interface Debug Commands Debug Cable Modem Ranging Messages This command acti vates deb ugging of ranging messages from cable modems on the HFC network. When this command is activ ated, ranging messages gener[...]

4-53 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Using Cable Interface Debug Commands Debug Spectrum Management This command activ ates deb ugging of spectrum management (frequency agility) on the HFC netw ork. When this command is acti v ated, messages generated becau[...]

4-54 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing the Cisco uBR7246 VXR Clock Card Debug Upstream Channel Description (UCD) Messages This command acti vates deb ugging of upstream channel descriptor (UCD) messages. UCD messages contain information about upstrea[...]

4-55 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing the Cisco uBR7246 VXR Clock Card Force Alternate Clock T o select the external timing source when the clock card is in holdov er mode, use the cable clock f orce global conf iguration command. T o disable the se[...]

4-56 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing the Cisco uBR7246 VXR Clock Card The follo wing sample output from the sho w cable clock command sho ws both external sources are av ailable and the clock card is pro viding the clock reference: Router# show cab[...]

4-57 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing the Cisco uBR7246 VXR Clock Card The follo wing is sample output from the show diag command displaying diagnostic information for the cable clock card: router# show diag Clockcard: National clock card with T1 co[...]

4-58 Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide 78-5897-01 Chapter 4 Troubleshooting the System Managing the Cisco uBR7246 VXR Clock Card Show Clock Frames T o display information about the midplane TDM clock reference, use the show frame-clocks pri vile ged EXEC command. show frame-clocks The follo wing sample out[...]