Administrator Guide

Displaying CoPP Configuration .............................................................................................................................245
12 Data Center Bridging (DCB).....................................................................................................................248
Ethernet Enhancements in Data Center Bridging.....................................................................................................248
Priority-Based Flow Control...................................................................................................................................249
Enhanced Transmission Selection.........................................................................................................................250
Data Center Bridging Exchange Protocol (DCBx)...............................................................................................251
Data Center Bridging in a Traffic Flow................................................................................................................. 252
Enabling Data Center Bridging.....................................................................................................................................252
DCB Maps and its Attributes................................................................................................................................. 253
Data Center Bridging: Default Configuration.............................................................................................................254
Configuring Priority-Based Flow Control....................................................................................................................254
Configuring Lossless Queues.................................................................................................................................255
Configuring PFC in a DCB Map...................................................................................................................................256
PFC Configuration Notes....................................................................................................................................... 256
PFC Prerequisites and Restrictions.......................................................................................................................257
Applying a DCB Map on a Port.................................................................................................................................... 257
Configuring PFC without a DCB Map.........................................................................................................................258
Configuring Lossless QueuesExample:................................................................................................................. 258
Priority-Based Flow Control Using Dynamic Buffer Method...................................................................................260
Pause and Resume of Traffic.................................................................................................................................260
Buffer Sizes for Lossless or PFC Packets............................................................................................................260
Behavior of Tagged Packets.........................................................................................................................................261
Configuration Example for DSCP and PFC Priorities................................................................................................ 261
Using PFC to Manage Converged Ethernet Traffic................................................................................................. 262
Configure Enhanced Transmission Selection.............................................................................................................262
ETS Prerequisites and Restrictions.......................................................................................................................262
Creating an ETS Priority Group............................................................................................................................. 262
ETS Operation with DCBx......................................................................................................................................264
Configuring Bandwidth Allocation for DCBx CIN................................................................................................ 264
Configuring ETS in a DCB Map............................................................................................................................. 265
Hierarchical Scheduling in ETS Output Policies.........................................................................................................266
Using ETS to Manage Converged Ethernet Traffic..................................................................................................267
Applying DCB Policies in a Switch Stack....................................................................................................................267
Configure a DCBx Operation........................................................................................................................................267
DCBx Operation.......................................................................................................................................................267
DCBx Port Roles......................................................................................................................................................268
DCB Configuration Exchange................................................................................................................................ 269
Configuration Source Election............................................................................................................................... 269
Propagation of DCB Information........................................................................................................................... 270
Auto-Detection and Manual Configuration of the DCBx Version......................................................................270
DCBx Example.......................................................................................................................................................... 271
DCBx Prerequisites and Restrictions..................................................................................................................... 271
Configuring DCBx.....................................................................................................................................................271
Verifying the DCB Configuration................................................................................................................................. 275
QoS dot1p Traffic Classification and Queue Assignment.........................................................................................284
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