Concept Guide

Priority-Based Flow Control................................................................................................................................... 275
Enhanced Transmission Selection..........................................................................................................................276
Data Center Bridging Exchange Protocol (DCBx)............................................................................................... 277
Data Center Bridging in a Trac Flow...................................................................................................................278
Enabling Data Center Bridging..................................................................................................................................... 278
DCB Maps and its Attributes..................................................................................................................................279
QoS dot1p Trac Classication and Queue Assignment..........................................................................................280
Data Center Bridging: Default Conguration.............................................................................................................. 281
Conguring Priority-Based Flow Control.....................................................................................................................281
Conguring Lossless Queues................................................................................................................................. 282
Conguring PFC in a DCB Map................................................................................................................................... 283
PFC Conguration Notes........................................................................................................................................283
PFC Prerequisites and Restrictions....................................................................................................................... 284
Applying a DCB Map on a Port.................................................................................................................................... 284
Priority-Based Flow Control Using Dynamic Buer Method....................................................................................285
Pause and Resume of Trac..................................................................................................................................285
Buer Sizes for Lossless or PFC Packets............................................................................................................ 285
Conguring PFC without a DCB Map.........................................................................................................................286
Conguring Lossless QueuesExample:..................................................................................................................286
Behavior of Tagged Packets.........................................................................................................................................288
Conguration Example for DSCP and PFC Priorities................................................................................................288
Using PFC to Manage Converged Ethernet Trac...................................................................................................289
Congure Enhanced Transmission Selection..............................................................................................................289
ETS Prerequisites and Restrictions....................................................................................................................... 290
Creating an ETS Priority Group............................................................................................................................. 290
ETS Operation with DCBx.......................................................................................................................................291
Conguring Bandwidth Allocation for DCBx CIN................................................................................................. 291
Conguring ETS in a DCB Map..............................................................................................................................292
Hierarchical Scheduling in ETS Output Policies...................................................................................................294
Using ETS to Manage Converged Ethernet Trac.............................................................................................294
Applying DCB Policies in a Switch Stack.................................................................................................................... 294
Congure a DCBx Operation........................................................................................................................................294
DCBx Operation.......................................................................................................................................................295
DCBx Port Roles......................................................................................................................................................295
DCB Conguration Exchange................................................................................................................................ 296
Conguration Source Election................................................................................................................................297
Propagation of DCB Information............................................................................................................................297
Auto-Detection and Manual Conguration of the DCBx Version...................................................................... 298
DCBx Example......................................................................................................................................................... 298
DCBx Prerequisites and Restrictions.....................................................................................................................299
Conguring DCBx....................................................................................................................................................299
Verifying the DCB Conguration................................................................................................................................. 303
QoS dot1p Trac Classication and Queue Assignment............................................................................................311
Conguring the Dynamic Buer Method.................................................................................................................... 312
Sample DCB Conguration............................................................................................................................................313
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