Concept Guide

Data Center Bridging Exchange Protocol (DCBx)...............................................................................................273
Data Center Bridging in a Trac Flow...................................................................................................................274
Enabling Data Center Bridging......................................................................................................................................274
DCB Maps and its Attributes..................................................................................................................................275
Data Center Bridging: Default Conguration..............................................................................................................276
Conguring Priority-Based Flow Control.................................................................................................................... 276
Conguring Lossless Queues..................................................................................................................................277
Conguring PFC in a DCB Map....................................................................................................................................278
PFC Conguration Notes........................................................................................................................................278
PFC Prerequisites and Restrictions....................................................................................................................... 279
Applying a DCB Map on a Port.................................................................................................................................... 279
Conguring PFC without a DCB Map.........................................................................................................................280
Conguring Lossless QueuesExample:..................................................................................................................280
Priority-Based Flow Control Using Dynamic Buer Method.................................................................................... 281
Pause and Resume of Trac..................................................................................................................................282
Buer Sizes for Lossless or PFC Packets.............................................................................................................282
Behavior of Tagged Packets.........................................................................................................................................282
Conguration Example for DSCP and PFC Priorities................................................................................................283
Using PFC to Manage Converged Ethernet Trac...................................................................................................284
Congure Enhanced Transmission Selection..............................................................................................................284
ETS Prerequisites and Restrictions....................................................................................................................... 284
Creating an ETS Priority Group..............................................................................................................................284
ETS Operation with DCBx......................................................................................................................................286
Conguring Bandwidth Allocation for DCBx CIN................................................................................................ 286
Conguring ETS in a DCB Map..............................................................................................................................287
Hierarchical Scheduling in ETS Output Policies......................................................................................................... 288
Using ETS to Manage Converged Ethernet Trac...................................................................................................289
Applying DCB Policies in a Switch Stack.................................................................................................................... 289
Congure a DCBx Operation........................................................................................................................................289
DCBx Operation.......................................................................................................................................................289
DCBx Port Roles......................................................................................................................................................290
DCB Conguration Exchange................................................................................................................................. 291
Conguration Source Election................................................................................................................................ 291
Propagation of DCB Information............................................................................................................................292
Auto-Detection and Manual Conguration of the DCBx Version...................................................................... 292
DCBx Example..........................................................................................................................................................293
DCBx Prerequisites and Restrictions.....................................................................................................................293
Conguring DCBx....................................................................................................................................................293
Verifying the DCB Conguration..................................................................................................................................297
Sample DCB Conguration...........................................................................................................................................305
PFC and ETS Conguration Command Examples...............................................................................................307
QoS dot1p Trac Classication and Queue Assignment.......................................................................................... 307
Conguring the Dynamic Buer Method................................................................................................................... 308
13 Dynamic Host Conguration Protocol (DHCP)..........................................................................................310
DHCP Packet Format and Options.............................................................................................................................. 310
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