Concept Guide

Enhanced Transmission Selection...........................................................................................................................281
Data Center Bridging Exchange Protocol (DCBx)...............................................................................................282
Data Center Bridging in a Trac Flow...................................................................................................................283
Enabling Data Center Bridging..................................................................................................................................... 283
DCB Maps and its Attributes..................................................................................................................................284
Data Center Bridging: Default Conguration..............................................................................................................285
Conguring Priority-Based Flow Control....................................................................................................................285
Conguring Lossless Queues................................................................................................................................. 286
Conguring PFC in a DCB Map....................................................................................................................................287
PFC Conguration Notes........................................................................................................................................287
PFC Prerequisites and Restrictions....................................................................................................................... 288
Applying a DCB Map on a Port.................................................................................................................................... 288
Conguring PFC without a DCB Map.........................................................................................................................289
Conguring Lossless QueuesExample:..................................................................................................................289
Priority-Based Flow Control Using Dynamic Buer Method.................................................................................... 291
Pause and Resume of Trac.................................................................................................................................. 291
Buer Sizes for Lossless or PFC Packets............................................................................................................. 291
Behavior of Tagged Packets.........................................................................................................................................292
Conguration Example for DSCP and PFC Priorities................................................................................................292
Using PFC to Manage Converged Ethernet Trac...................................................................................................293
Congure Enhanced Transmission Selection..............................................................................................................293
ETS Prerequisites and Restrictions....................................................................................................................... 294
Creating an ETS Priority Group..............................................................................................................................294
ETS Operation with DCBx......................................................................................................................................295
Conguring Bandwidth Allocation for DCBx CIN................................................................................................ 295
Conguring ETS in a DCB Map..............................................................................................................................296
Hierarchical Scheduling in ETS Output Policies......................................................................................................... 297
Using ETS to Manage Converged Ethernet Trac...................................................................................................298
Applying DCB Policies in a Switch Stack.................................................................................................................... 298
Congure a DCBx Operation........................................................................................................................................298
DCBx Operation.......................................................................................................................................................299
DCBx Port Roles......................................................................................................................................................299
DCB Conguration Exchange................................................................................................................................ 300
Conguration Source Election................................................................................................................................ 301
Propagation of DCB Information............................................................................................................................ 301
Auto-Detection and Manual Conguration of the DCBx Version.......................................................................301
DCBx Example......................................................................................................................................................... 302
DCBx Prerequisites and Restrictions.....................................................................................................................302
Conguring DCBx....................................................................................................................................................303
Verifying the DCB Conguration................................................................................................................................. 306
QoS dot1p Trac Classication and Queue Assignment...........................................................................................316
Conguring the Dynamic Buer Method.................................................................................................................... 317
Sample DCB Conguration............................................................................................................................................318
PFC and ETS Conguration Command Examples............................................................................................... 319
13 Dynamic Host Conguration Protocol (DHCP).........................................................................................320
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