Concept Guide

Conguring CoPP for CPU Queues...................................................................................................................... 269
Protocol to CPU Queue Mapping.......................................................................................................................... 270
Conguring Protocol to CPU Queue Mapping.....................................................................................................270
Displaying CoPP Conguration .............................................................................................................................. 271
12 Data Center Bridging (DCB)..................................................................................................................... 273
Ethernet Enhancements in Data Center Bridging......................................................................................................273
Priority-Based Flow Control....................................................................................................................................274
Enhanced Transmission Selection..........................................................................................................................275
Data Center Bridging Exchange Protocol (DCBx)...............................................................................................276
Data Center Bridging in a Trac Flow...................................................................................................................277
Enabling Data Center Bridging......................................................................................................................................277
DCB Maps and its Attributes..................................................................................................................................278
Data Center Bridging: Default Conguration..............................................................................................................278
Conguring Priority-Based Flow Control.................................................................................................................... 279
Conguring Lossless Queues................................................................................................................................. 280
Conguring PFC in a DCB Map....................................................................................................................................281
PFC Conguration Notes........................................................................................................................................ 281
PFC Prerequisites and Restrictions....................................................................................................................... 282
Applying a DCB Map on a Port.................................................................................................................................... 282
Conguring PFC without a DCB Map.........................................................................................................................283
Conguring PFC Asymmetric.......................................................................................................................................283
Priority-Based Flow Control Using Dynamic Buer Method....................................................................................284
Pause and Resume of Trac..................................................................................................................................284
Buer Sizes for Lossless or PFC Packets.............................................................................................................284
Shared headroom for lossless or PFC packets.......................................................................................................... 285
Example Scenario.................................................................................................................................................... 285
Conguring Shared Head Room Buer.................................................................................................................287
Viewing Shared Head Room Usage.......................................................................................................................287
Monitoring Buer Statistics for Tracking Purposes.............................................................................................287
Behavior of Tagged Packets.........................................................................................................................................288
SNMP Support for PFC and Buer Statistics Tracking............................................................................................288
Performing PFC Using DSCP Bits Instead of 802.1p Bits.........................................................................................289
Conguration Example for DSCP and PFC Priorities................................................................................................290
Using PFC to Manage Converged Ethernet Trac.................................................................................................. 290
Generation of PFC for a Priority for Untagged Packets...........................................................................................290
Congure Enhanced Transmission Selection............................................................................................................. 290
Creating an ETS Priority Group.............................................................................................................................. 291
ETS Operation with DCBx......................................................................................................................................292
Conguring ETS in a DCB Map..............................................................................................................................292
Hierarchical Scheduling in ETS Output Policies......................................................................................................... 293
Using ETS to Manage Converged Ethernet Trac...................................................................................................294
Applying DCB Policies in a Switch Stack.................................................................................................................... 294
Congure a DCBx Operation........................................................................................................................................294
DCBx Operation.......................................................................................................................................................295
DCBx Port Roles......................................................................................................................................................295
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