Users Guide

Implementation Information..........................................................................................................................................623
Congure Per-VLAN Spanning Tree Plus................................................................................................................... 623
Related Conguration Tasks...................................................................................................................................623
Enabling PVST+............................................................................................................................................................. 623
Disabling PVST+.............................................................................................................................................................624
Inuencing PVST+ Root Selection...............................................................................................................................624
Modifying Global PVST+ Parameters..........................................................................................................................626
Modifying Interface PVST+ Parameters..................................................................................................................... 627
Conguring an EdgePort.............................................................................................................................................. 628
PVST+ in Multi-Vendor Networks............................................................................................................................... 628
Enabling PVST+ Extend System ID............................................................................................................................. 628
PVST+ Sample Congurations.....................................................................................................................................629
39 Quality of Service (QoS)..........................................................................................................................632
Implementation Information..........................................................................................................................................634
Port-Based QoS Congurations.................................................................................................................................. 634
Setting dot1p Priorities for Incoming Trac......................................................................................................... 634
Honoring dot1p Priorities on Ingress Trac..........................................................................................................635
Conguring Port-Based Rate Policing.................................................................................................................. 636
Conguring Port-Based Rate Shaping..................................................................................................................636
Policy-Based QoS Congurations................................................................................................................................637
Classify Trac..........................................................................................................................................................638
Create a QoS Policy................................................................................................................................................. 641
Create Policy Maps..................................................................................................................................................643
DSCP Color Maps..........................................................................................................................................................647
Creating a DSCP Color Map...................................................................................................................................647
Displaying DSCP Color Maps................................................................................................................................. 648
Displaying a DSCP Color Policy Conguration ....................................................................................................648
Enabling QoS Rate Adjustment....................................................................................................................................649
Enabling Strict-Priority Queueing................................................................................................................................650
Weighted Random Early Detection............................................................................................................................. 650
Creating WRED Proles...........................................................................................................................................651
Applying a WRED Prole to Trac........................................................................................................................652
Displaying Default and Congured WRED Proles..............................................................................................652
Displaying WRED Drop Statistics...........................................................................................................................652
Displaying egress–queue Statistics....................................................................................................................... 653
Pre-Calculating Available QoS CAM Space................................................................................................................653
Conguring Weights and ECN for WRED ................................................................................................................. 654
Global Service Pools With WRED and ECN Settings......................................................................................... 655
Conguring WRED and ECN Attributes..................................................................................................................... 656
Guidelines for Conguring ECN for Classifying and Color-Marking Packets.........................................................656
Sample conguration to mark non-ecn packets as “yellow” with Multiple trac class..................................657
Classifying Incoming Packets Using ECN and Color-Marking............................................................................657
Sample conguration to mark non-ecn packets as “yellow” with single trac class..................................... 659
Applying Layer 2 Match Criteria on a Layer 3 Interface........................................................................................... 660
Applying DSCP and VLAN Match Criteria on a Service Queue............................................................................... 661
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