Concept Guide

Table Of Contents
DCB Configuration Exchange................................................................................................................................ 260
Configuration Source Election............................................................................................................................... 260
Propagation of DCB Information............................................................................................................................261
Auto-Detection and Manual Configuration of the DCBx Version.................................................................. 261
Behavior of Tagged Packets.................................................................................................................................. 262
Configuration Example for DSCP and PFC Priorities.......................................................................................262
DCBx Example............................................................................................................................................................263
DCBx Prerequisites and Restrictions................................................................................................................... 263
Configuring DCBx......................................................................................................................................................264
Verifying the DCB Configuration.................................................................................................................................267
Performing PFC Using DSCP Bits Instead of 802.1p Bits..................................................................................... 276
PFC and ETS Configuration Examples....................................................................................................................... 277
Using PFC and ETS to Manage Data Center Traffic..............................................................................................277
Using PFC and ETS to Manage Converged Ethernet Traffic.........................................................................278
Hierarchical Scheduling in ETS Output Policies.................................................................................................279
Priority-Based Flow Control Using Dynamic Buffer Method................................................................................279
Configuring the Dynamic Buffer Method..................................................................................................................280
Chapter 12: Debugging and Diagnostics..................................................................................... 282
Offline Diagnostics..........................................................................................................................................................282
Running Port Extender Offline Diagnostics on the Switch.............................................................................282
Running Offline Diagnostics on a Standalone Switch...................................................................................... 288
TRACE Logs..................................................................................................................................................................... 308
Auto Save on Reload, Crash, or Rollover............................................................................................................ 308
Uploading Trace Logs.............................................................................................................................................. 308
Last Restart Reason.......................................................................................................................................................309
show hardware Commands.......................................................................................................................................... 309
Environmental Monitoring.............................................................................................................................................. 311
Displaying Port Extender Environment Information ......................................................................................... 312
Display Power Supply Status.................................................................................................................................. 312
Display Fan Status..................................................................................................................................................... 313
Display Transceiver Type......................................................................................................................................... 313
Recognize an Over-Temperature Condition....................................................................................................... 315
Troubleshoot an Over-Temperature Condition.................................................................................................. 315
Troubleshooting Packet Loss........................................................................................................................................317
Displaying Drop Counters.........................................................................................................................................318
Displaying Dataplane Statistics...............................................................................................................................319
Displaying Line-Card Counters.............................................................................................................................. 320
Accessing Application Core Dumps.............................................................................................................................321
Mini Core Dumps.............................................................................................................................................................322
Full Kernel Core Dumps................................................................................................................................................. 322
Enabling TCP Dumps......................................................................................................................................................323
Accessing Port Extender Core and Mini Core Dumps........................................................................................... 323
Chapter 13: Dynamic Host Configuration Protocol (DHCP)........................................................ 324
DHCP Packet Format and Options.............................................................................................................................324
Assign an IP Address using DHCP.............................................................................................................................. 325
Implementation Information......................................................................................................................................... 326
Configure the System to be a DHCP Server............................................................................................................327
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