Cisco Systems uBR7200 Series manual Blind Strategies and Time Scheduled Combined, Token-bucket

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Chapter 4 Troubleshooting the System

Managing Cable Modems on the HFC Network

To configure this, use the following command in cable interface configuration mode.

Table 4-12 Instructions to Conﬁgure Upstream Shaping

Command	Purpose

CMTS01(config-if)#[no]cable upstream <n1> rate-limit	Enables or disables DOCSIS rate limiting or
[token-bucket]	shaping on an upstream channel. <n1> depends on
	the number of upstream channels on the specific
	cable modem card.

Using Cisco IOS Release 12.0(5)T1 or higher, the software supports:

•Generic calendar queuing routines

•New token bucket policing function

•Grant shaping application of the calendar queues

•Upstream rate shaping option to the token-bucket keyword

•A default state change from 1 second burst policing to token-bucket with shaping

Tips Upstream grant shaping is per CM (SID). Shaping can be enabled or disabled for the token-bucket algorithm.

Note Before the introduction of this feature, the CMTS would drop bandwidth requests from a CM it detected as exceeding its configured peak upstream rate. Such request dropping affects the throughput performance of IP-based protocols such as FTP, TCP, and SMTP. With this feature, the CMTS can shape (buffer) the grants for a CM that is exceeding its upstream rate, rather than dropping the bandwidth requests.

CMTS01# show interface c3/0 sid 1 counters

Sid	Inpackets	Inoctets	Outpackets Outoctets		Ratelimit	Ratelimit
					BWReqDrop	DSPktDrop
1	67859	99158800	67570	98734862	2579	0

Configure Spectrum Management (without the Cisco MC16S Cable Modem Card)

Blind Strategies and Time Scheduled Combined

The Cisco uBR7200 series software supports combined blind and time scheduled spectrum management using Cisco IOS Release 12.0(5)T1 images or higher:

•Using blind spectrum management, the number of lost station management messages exceeding a configured threshold (default = 10) initiates an upstream channel frequency reassignment. The Cisco uBR7200 series moves all cable modems on the upstream port by sending UCD messages that contain the next frequency and input power level defined in the spectrum management group. The frequency change occurs rapidly without data loss and minimal latency.

Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide

	78-5897-01	4-11

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Contents Troubleshooting the System Managing Cable Modems on the HFC Network Configure Sync Message IntervalVerify Sync Message Interval Activate Cable Modem AuthenticationVerify Cable Modem Authentication Activate Cable Modem Upstream Address VerificationVerify Cable Modem Upstream Address Verification CMTS01config-if#cable source-verify dhcpCMTS01config-if#no cable source-verify Automatic CMTS01config-if#no cable insertion-intervalCMTS01config-if#cable insertion-interval max CMTS01config-if#cable insertion-intervalConfigure Per Modem Filters Configure access lists to be specified on a CMTS01config-if#cable registration-timeout n Configure Cable Modem Registration TimeoutClear Cable Modem Reset Clear Cable Modem Counters Verify Clear Cable Modem ResetVerify Clear Cable Modem Counters Configure Traffic ShapingConfigure Downstream Rate Limiting and Shaping Configure Upstream Rate Limiting and ShapingCMTS01# show interface c3/0 sid 1 counters CMTS01config-if#nocable upstream n1 rate-limitBlind Strategies and Time Scheduled Combined Token-bucketGuided Frequency Hop Field Description Sample outputShow Cable Hop Command Spectrum Management Debug and Test Commands14 Show Cable Hop Parameter Descriptions Polling Cable Modems Debug and Test CommandsVerifying Remote Query Information Enable SnmpConfigure Remote Modem Monitoring Allows you to conﬁgure accessMonitoring and Maintaining Remote Querying Understanding Show Command ResponsesGeneral Show Commands Show Cable Modem See the sample command output below Page SID Cable modem cable 3/0 upstream 0 offline Show Cable Modem MaintenanceCable modem cable 3/0 upstream 0 unregistered Show Interface Cable UBR7200#show cable modem maintenanceMTU CRC Router# show interface cable 6/0 downstream Field Description18 Show Interface Cable Upstream Command Field Descriptions ATP Enhanced Show Interface Upstream Output Cable slot 3, port Show Interface Cable SIDConnectivity Router# show interface c3/0 sid counters verboseShow Router# show interface c3/0 sid connectivityRouter# show interface c3/0 sid 1 counters UBR7200#show cable qos profile Troubleshooting Using Cable Flap ListsShow Cable QoS Profile Page Page UBR7200#show cable flap Display the Flap ListMAC ID Statistic DescriptionPlant troubleshooting. The CRC counter indicates Troubleshoot with the Flap List Verify Cable Flap List Insertion Time Set Cable Flap List AgingSet Cable Flap List Insertion Time Verify Cable Flap List AgingSet Cable Flap List Miss Threshold Set Cable Flap List Power Adjustment ThresholdVerify Cable Flap List Power Adjustment Threshold Verify Cable Flap List Size Set Cable Flap List SizeClear Cable Flap List Verify Cable Flap List Miss ThresholdCustomize Other Flap List Values and Related Commands Performing Amplitude Averaging Enable or Disable Power AdjustmentSyntax Valid Values Set Frequency Threshold to Affect Power AdjustmentStep Command Purpose Setting Downstream Test SignalsConfigure Unmodulated Test Signals Pinging Unresponsive Cable Modems Configure Prbs Test SignalsVerify Test Signal Output Step CommandDebug Cable ARP Requests Using Cable Interface Debug CommandsVerify the Ping Debug Baseline Privacy Activity Debug Cable MAC Protocol ErrorsDebug Environmental Monitor Messages Activate Debug of Baseline PrivacyActivate QoS Debug Debug Cable MapsDebug Cable Modems Debug Cable PHY MessagesDebug Cable Modem Registration Requests Debug Cable Modem Reset MessagesDebug Cable Modem Ranging Messages Debug Upstream MessagesDebug Upstream Channel Change UCC Messages Debug Spectrum ManagementDebug Channel Allocations Debug Cmts TransmissionsShow diag Show frame-clocks Show tech support Show version Managing the Cisco uBR7246 VXR Clock CardDebug Upstream Channel Description UCD Messages Clear Clock CountersCable clock force primary secondary no cable clock force Force Alternate ClockSet Midplane TDM Clock as Primary Reference Display Clock ValuesShow controllers clock-reference Show Clock Diagnostic InformationShow Clock Hardware Information and Register Values Router# show cable clock33 describes the fields shown in the show diag display Router# show frame-clocks Show Clock FramesShow General Information