Users Guide

12 Data Center Bridging (DCB)..................................................................................................................... 242
Ethernet Enhancements in Data Center Bridging......................................................................................................242
Priority-Based Flow Control................................................................................................................................... 243
Enhanced Transmission Selection..........................................................................................................................244
Data Center Bridging Exchange Protocol (DCBx)...............................................................................................245
Data Center Bridging in a Trac Flow...................................................................................................................246
Enabling Data Center Bridging..................................................................................................................................... 246
DCB Maps and its Attributes..................................................................................................................................247
Data Center Bridging: Default Conguration..............................................................................................................248
Conguring Priority-Based Flow Control.................................................................................................................... 248
Conguring Lossless Queues....................................................................................................................................... 249
Conguring PFC in a DCB Map....................................................................................................................................251
PFC Conguration Notes........................................................................................................................................ 251
PFC Prerequisites and Restrictions....................................................................................................................... 252
Conguring PFC without a DCB Map.........................................................................................................................252
Conguring Lossless QueuesExample:..................................................................................................................252
Priority-Based Flow Control Using Dynamic Buer Method..............................................................................254
Behavior of Tagged Packets.........................................................................................................................................255
Conguration Example for DSCP and PFC Priorities................................................................................................255
SNMP Support for PFC and Buer Statistics Tracking........................................................................................... 256
Performing PFC Using DSCP Bits Instead of 802.1p Bits.........................................................................................257
PFC and ETS Conguration Examples........................................................................................................................257
Using PFC to Manage Converged Ethernet Trac...................................................................................................257
Operations on Untagged Packets................................................................................................................................258
Generation of PFC for a Priority for Untagged Packets...........................................................................................258
Congure Enhanced Transmission Selection..............................................................................................................258
ETS Prerequisites and Restrictions....................................................................................................................... 258
Creating an ETS Priority Group............................................................................................................................. 259
ETS Operation with DCBx......................................................................................................................................260
Conguring Bandwidth Allocation for DCBx CIN................................................................................................ 260
Conguring ETS in a DCB Map.............................................................................................................................. 261
Hierarchical Scheduling in ETS Output Policies......................................................................................................... 262
Using ETS to Manage Converged Ethernet Trac...................................................................................................263
Applying DCB Policies in a Switch Stack.................................................................................................................... 263
Congure a DCBx Operation........................................................................................................................................263
DCBx Operation....................................................................................................................................................... 263
DCBx Port Roles...................................................................................................................................................... 264
DCB Conguration Exchange................................................................................................................................ 265
Conguration Source Election............................................................................................................................... 265
Propagation of DCB Information........................................................................................................................... 266
Auto-Detection and Manual Conguration of the DCBx Version...................................................................... 266
DCBx Example..........................................................................................................................................................267
DCBx Prerequisites and Restrictions.....................................................................................................................267
Conguring DCBx.................................................................................................................................................... 267
Verifying the DCB Conguration.................................................................................................................................. 271
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