Users Guide

Ethernet Enhancements in Data Center Bridging.....................................................................................................239
Priority-Based Flow Control...................................................................................................................................240
Enhanced Transmission Selection..........................................................................................................................241
Data Center Bridging Exchange Protocol (DCBx).............................................................................................. 242
Data Center Bridging in a Traffic Flow................................................................................................................. 243
Enabling Data Center Bridging.....................................................................................................................................243
DCB Maps and its Attributes................................................................................................................................. 244
Data Center Bridging: Default Configuration.............................................................................................................245
Configuring Priority-Based Flow Control....................................................................................................................245
Configuring Lossless Queues....................................................................................................................................... 246
Configuring PFC in a DCB Map................................................................................................................................... 248
PFC Configuration Notes....................................................................................................................................... 248
PFC Prerequisites and Restrictions.......................................................................................................................249
Configuring PFC without a DCB Map.........................................................................................................................249
Configuring Lossless QueuesExample:................................................................................................................. 249
Priority-Based Flow Control Using Dynamic Buffer Method..............................................................................251
Behavior of Tagged Packets........................................................................................................................................252
Configuration Example for DSCP and PFC Priorities............................................................................................... 252
SNMP Support for PFC and Buffer Statistics Tracking...........................................................................................253
Performing PFC Using DSCP Bits Instead of 802.1p Bits........................................................................................254
PFC and ETS Configuration Examples....................................................................................................................... 254
Using PFC to Manage Converged Ethernet Traffic................................................................................................. 254
Operations on Untagged Packets............................................................................................................................... 255
Generation of PFC for a Priority for Untagged Packets..........................................................................................255
Configure Enhanced Transmission Selection.............................................................................................................255
ETS Prerequisites and Restrictions.......................................................................................................................255
Creating an ETS Priority Group.............................................................................................................................256
ETS Operation with DCBx......................................................................................................................................257
Configuring Bandwidth Allocation for DCBx CIN................................................................................................ 257
Configuring ETS in a DCB Map............................................................................................................................. 258
Hierarchical Scheduling in ETS Output Policies.........................................................................................................259
Using ETS to Manage Converged Ethernet Traffic..................................................................................................260
Applying DCB Policies in a Switch Stack....................................................................................................................260
Configure a DCBx Operation....................................................................................................................................... 260
DCBx Operation.......................................................................................................................................................260
DCBx Port Roles.......................................................................................................................................................261
DCB Configuration Exchange................................................................................................................................ 262
Configuration Source Election............................................................................................................................... 262
Propagation of DCB Information........................................................................................................................... 263
Auto-Detection and Manual Configuration of the DCBx Version..................................................................... 263
DCBx Example......................................................................................................................................................... 264
DCBx Prerequisites and Restrictions.................................................................................................................... 264
Configuring DCBx....................................................................................................................................................264
Verifying the DCB Configuration.................................................................................................................................268
QoS dot1p Traffic Classification and Queue Assignment......................................................................................... 277
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