Concept Guide

Enhanced Transmission Selection..........................................................................................................................252
Data Center Bridging Exchange Protocol (DCBx)...............................................................................................253
Data Center Bridging in a Trac Flow.................................................................................................................. 254
Enabling Data Center Bridging.....................................................................................................................................254
DCB Maps and its Attributes................................................................................................................................. 255
Data Center Bridging: Default Conguration..............................................................................................................256
Conguring Priority-Based Flow Control....................................................................................................................256
Conguring Lossless Queues..................................................................................................................................257
Conguring PFC in a DCB Map................................................................................................................................... 258
PFC Conguration Notes....................................................................................................................................... 258
PFC Prerequisites and Restrictions.......................................................................................................................259
Applying a DCB Map on a Port....................................................................................................................................260
Conguring PFC without a DCB Map.........................................................................................................................260
Conguring Lossless QueuesExample:.................................................................................................................. 261
Priority-Based Flow Control Using Dynamic Buer Method....................................................................................262
Pause and Resume of Trac..................................................................................................................................262
Buer Sizes for Lossless or PFC Packets............................................................................................................ 262
Behavior of Tagged Packets.........................................................................................................................................263
Conguration Example for DSCP and PFC Priorities................................................................................................263
SNMP Support for PFC and Buer Statistics Tracking............................................................................................264
Performing PFC Using DSCP Bits Instead of 802.1p Bits.........................................................................................264
PFC and ETS Conguration Examples........................................................................................................................265
Using PFC to Manage Converged Ethernet Trac.................................................................................................. 265
Operations on Untagged Packets................................................................................................................................265
Generation of PFC for a Priority for Untagged Packets...........................................................................................266
Congure Enhanced Transmission Selection..............................................................................................................266
ETS Prerequisites and Restrictions....................................................................................................................... 266
Creating an ETS Priority Group............................................................................................................................. 266
ETS Operation with DCBx......................................................................................................................................268
Conguring Bandwidth Allocation for DCBx CIN................................................................................................ 268
Conguring ETS in a DCB Map..............................................................................................................................269
Hierarchical Scheduling in ETS Output Policies......................................................................................................... 270
Using ETS to Manage Converged Ethernet Trac....................................................................................................271
Applying DCB Policies in a Switch Stack..................................................................................................................... 271
Congure a DCBx Operation.........................................................................................................................................271
DCBx Operation........................................................................................................................................................271
DCBx Port Roles...................................................................................................................................................... 272
DCB Conguration Exchange.................................................................................................................................273
Conguration Source Election................................................................................................................................273
Propagation of DCB Information............................................................................................................................274
Auto-Detection and Manual Conguration of the DCBx Version.......................................................................274
DCBx Example..........................................................................................................................................................275
DCBx Prerequisites and Restrictions.....................................................................................................................275
Conguring DCBx.................................................................................................................................................... 275
Verifying the DCB Conguration..................................................................................................................................279
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