Users Guide

Inuencing PVST+ Root Selection.............................................................................................................................. 680
Modifying Global PVST+ Parameters..........................................................................................................................682
Modifying Interface PVST+ Parameters..................................................................................................................... 683
Conguring an EdgePort.............................................................................................................................................. 684
PVST+ in Multi-Vendor Networks............................................................................................................................... 684
Enabling PVST+ Extend System ID............................................................................................................................. 684
PVST+ Sample Congurations.....................................................................................................................................685
43 Quality of Service (QoS)..........................................................................................................................688
Implementation Information......................................................................................................................................... 690
Port-Based QoS Congurations.................................................................................................................................. 690
Setting dot1p Priorities for Incoming Trac.........................................................................................................690
Honoring dot1p Priorities on Ingress Trac.......................................................................................................... 691
Conguring Port-Based Rate Policing.................................................................................................................. 692
Conguring Port-Based Rate Shaping..................................................................................................................692
Policy-Based QoS Congurations................................................................................................................................693
Classify Trac..........................................................................................................................................................693
Create a QoS Policy................................................................................................................................................ 696
Create Policy Maps................................................................................................................................................. 699
DSCP Color Maps..........................................................................................................................................................702
Creating a DSCP Color Map...................................................................................................................................702
Displaying DSCP Color Maps................................................................................................................................. 703
Displaying a DSCP Color Policy Conguration .................................................................................................... 704
Enabling QoS Rate Adjustment....................................................................................................................................704
Enabling Strict-Priority Queueing................................................................................................................................ 705
Weighted Random Early Detection..............................................................................................................................705
Creating WRED Proles..........................................................................................................................................706
Applying a WRED Prole to Trac.........................................................................................................................707
Displaying Default and Congured WRED Proles.............................................................................................. 707
Displaying WRED Drop Statistics........................................................................................................................... 707
Displaying egress–queue Statistics....................................................................................................................... 708
Pre-Calculating Available QoS CAM Space................................................................................................................ 708
Conguring Weights and ECN for WRED ..................................................................................................................709
Global Service Pools With WRED and ECN Settings.......................................................................................... 710
Conguring WRED and ECN Attributes....................................................................................................................... 711
Guidelines for Conguring ECN for Classifying and Color-Marking Packets...........................................................711
Sample conguration to mark non-ecn packets as “yellow” with Multiple trac class.................................. 712
Classifying Incoming Packets Using ECN and Color-Marking............................................................................ 712
Sample conguration to mark non-ecn packets as “yellow” with single trac class...................................... 714
Applying Layer 2 Match Criteria on a Layer 3 Interface............................................................................................ 715
Applying DSCP and VLAN Match Criteria on a Service Queue................................................................................716
Classifying Incoming Packets Using ECN and Color-Marking...................................................................................717
Guidelines for Conguring ECN for Classifying and Color-Marking Packets..........................................................718
Sample conguration to mark non-ecn packets as “yellow” with Multiple trac class........................................ 719
Sample conguration to mark non-ecn packets as “yellow” with single trac class............................................ 719
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