Concept Guide

Disabling PVST+..............................................................................................................................................................719
Inuencing PVST+ Root Selection............................................................................................................................... 719
Modifying Global PVST+ Parameters...........................................................................................................................721
Modifying Interface PVST+ Parameters..................................................................................................................... 722
Conguring an EdgePort...............................................................................................................................................723
PVST+ in Multi-Vendor Networks................................................................................................................................723
Enabling PVST+ Extend System ID..............................................................................................................................723
PVST+ Sample Congurations..................................................................................................................................... 724
40 Quality of Service (QoS)..........................................................................................................................727
Implementation Information..........................................................................................................................................729
Port-Based QoS Congurations.................................................................................................................................. 729
Setting dot1p Priorities for Incoming Trac......................................................................................................... 729
Honoring dot1p Priorities on Ingress Trac..........................................................................................................730
Conguring Port-Based Rate Policing....................................................................................................................731
Conguring Port-Based Rate Shaping...................................................................................................................731
Policy-Based QoS Congurations................................................................................................................................732
Classify Trac.......................................................................................................................................................... 732
Dot1p to Queue Mapping Requirement.................................................................................................................736
Create a QoS Policy.................................................................................................................................................736
DSCP Color Maps....................................................................................................................................................739
Create Policy Maps...................................................................................................................................................741
Enabling QoS Rate Adjustment.................................................................................................................................... 744
Enabling Strict-Priority Queueing................................................................................................................................ 745
Queue Classication Requirements for PFC Functionality....................................................................................... 745
Support for marking dot1p value in L3 Input Qos Policy........................................................................................... 745
Weighted Random Early Detection..............................................................................................................................746
Creating WRED Proles.......................................................................................................................................... 747
Applying a WRED Prole to Trac.........................................................................................................................747
Displaying Default and Congured WRED Proles.............................................................................................. 748
Displaying WRED Drop Statistics........................................................................................................................... 748
Displaying egress–queue Statistics........................................................................................................................748
Pre-Calculating Available QoS CAM Space................................................................................................................ 749
Specifying Policy-Based Rate Shaping in Packets Per Second............................................................................... 750
Conguring Policy-Based Rate Shaping..................................................................................................................... 750
Conguring Weights and ECN for WRED .................................................................................................................. 751
Global Service Pools With WRED and ECN Settings...........................................................................................751
Conguring WRED and ECN Attributes......................................................................................................................752
Guidelines for Conguring ECN for Classifying and Color-Marking Packets......................................................... 753
Sample conguration to mark non-ecn packets as “yellow” with Multiple trac class..................................754
Classifying Incoming Packets Using ECN and Color-Marking............................................................................754
Sample conguration to mark non-ecn packets as “yellow” with single trac class......................................756
Applying Layer 2 Match Criteria on a Layer 3 Interface............................................................................................757
Managing Hardware Buer Statistics....................................................................................................................757
Enabling Buer Statistics Tracking .............................................................................................................................758
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