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Table Of Contents
Protocol to CPU Queue Mapping..........................................................................................................................237
Configuring Protocol to CPU Queue Mapping...................................................................................................238
Displaying CoPP Configuration .............................................................................................................................239
Chapter 12: Data Center Bridging (DCB).................................................................................... 241
Ethernet Enhancements in Data Center Bridging....................................................................................................241
Priority-Based Flow Control................................................................................................................................... 242
Enhanced Transmission Selection.........................................................................................................................243
Data Center Bridging Exchange Protocol (DCBx)............................................................................................ 244
Data Center Bridging in a Traffic Flow................................................................................................................ 245
Buffer Organization.................................................................................................................................................. 245
Enabling Data Center Bridging.....................................................................................................................................248
DCB Maps and its Attributes..................................................................................................................................248
Data Center Bridging: Default Configuration........................................................................................................... 249
Configuring Priority-Based Flow Control.................................................................................................................. 249
Configuring Lossless Queues................................................................................................................................. 250
Configuring PFC in a DCB Map....................................................................................................................................251
Applying a DCB Map on a Port....................................................................................................................................252
Configuring PFC without a DCB Map........................................................................................................................253
Priority-Based Flow Control Using Dynamic Buffer Method............................................................................... 255
Shared headroom for lossless or PFC packets........................................................................................................256
Configuring Shared Head Room Buffer............................................................................................................... 257
Viewing Shared Head Room Usage...................................................................................................................... 257
Monitoring Buffer Statistics for Tracking Purposes.........................................................................................258
Behavior of Tagged Packets........................................................................................................................................258
Configuration Example for DSCP and PFC Priorities.............................................................................................258
SNMP Support for PFC and Buffer Statistics Tracking....................................................................................... 259
Performing PFC Using DSCP Bits Instead of 802.1p Bits.....................................................................................260
PFC and ETS Configuration Examples.......................................................................................................................262
Using PFC to Manage Converged Ethernet Traffic...............................................................................................262
Operations on Untagged Packets...............................................................................................................................262
Generation of PFC for a Priority for Untagged Packets.......................................................................................263
Configure Enhanced Transmission Selection........................................................................................................... 263
Creating an ETS Priority Group............................................................................................................................. 263
ETS Operation with DCBx.......................................................................................................................................264
Configuring ETS in a DCB Map..............................................................................................................................264
Hierarchical Scheduling in ETS Output Policies...................................................................................................... 265
Using ETS to Manage Converged Ethernet Traffic............................................................................................... 266
Applying DCB Policies in a Switch Stack.................................................................................................................. 266
Configure a DCBx Operation........................................................................................................................................266
DCBx Operation.........................................................................................................................................................267
DCBx Port Roles........................................................................................................................................................267
DCB Configuration Exchange.................................................................................................................................268
Configuration Source Election............................................................................................................................... 268
Propagation of DCB Information...........................................................................................................................269
Auto-Detection and Manual Configuration of the DCBx Version..................................................................269
DCBx Example........................................................................................................................................................... 269
DCBx Prerequisites and Restrictions....................................................................................................................270
Configuring DCBx......................................................................................................................................................270
Verifying the DCB Configuration.................................................................................................................................274
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