Administrator Guide

Inuencing PVST+ Root Selection................................................................................................................................712
Modifying Global PVST+ Parameters...........................................................................................................................714
Modifying Interface PVST+ Parameters......................................................................................................................715
Conguring an EdgePort............................................................................................................................................... 716
PVST+ in Multi-Vendor Networks................................................................................................................................ 716
Enabling PVST+ Extend System ID.............................................................................................................................. 716
PVST+ Sample Congurations......................................................................................................................................717
42 Quality of Service (QoS)..........................................................................................................................720
Implementation Information..........................................................................................................................................722
Port-Based QoS Congurations...................................................................................................................................722
Setting dot1p Priorities for Incoming Trac......................................................................................................... 722
Honoring dot1p Priorities on Ingress Trac..........................................................................................................723
Conguring Port-Based Rate Policing...................................................................................................................724
Conguring Port-Based Rate Shaping.................................................................................................................. 724
Policy-Based QoS Congurations................................................................................................................................725
Classify Trac.......................................................................................................................................................... 725
Create a QoS Policy.................................................................................................................................................729
Create Policy Maps...................................................................................................................................................731
DSCP Color Maps..........................................................................................................................................................735
Creating a DSCP Color Map...................................................................................................................................735
Displaying DSCP Color Maps................................................................................................................................. 736
Displaying a DSCP Color Policy Conguration .................................................................................................... 736
Enabling QoS Rate Adjustment.................................................................................................................................... 737
Enabling Strict-Priority Queueing................................................................................................................................ 738
Weighted Random Early Detection..............................................................................................................................738
Creating WRED Proles..........................................................................................................................................739
Applying a WRED Prole to Trac........................................................................................................................ 740
Displaying Default and Congured WRED Proles.............................................................................................. 740
Displaying WRED Drop Statistics...........................................................................................................................740
Displaying egress–queue Statistics........................................................................................................................ 741
Pre-Calculating Available QoS CAM Space................................................................................................................. 741
Conguring Weights and ECN for WRED ..................................................................................................................742
Global Service Pools With WRED and ECN Settings.......................................................................................... 742
Conguring WRED and ECN Attributes......................................................................................................................743
Guidelines for Conguring ECN for Classifying and Color-Marking Packets......................................................... 744
Sample conguration to mark non-ecn packets as “yellow” with Multiple trac class..................................745
Classifying Incoming Packets Using ECN and Color-Marking............................................................................745
Sample conguration to mark non-ecn packets as “yellow” with single trac class...................................... 747
Applying Layer 2 Match Criteria on a Layer 3 Interface............................................................................................748
Applying DSCP and VLAN Match Criteria on a Service Queue............................................................................... 748
Classifying Incoming Packets Using ECN and Color-Marking..................................................................................749
Guidelines for Conguring ECN for Classifying and Color-Marking Packets..........................................................751
Sample conguration to mark non-ecn packets as “yellow” with Multiple trac class.........................................751
Sample conguration to mark non-ecn packets as “yellow” with single trac class............................................752
Enabling Buer Statistics Tracking .............................................................................................................................753
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