Concept Guide

Verify a Stack Conguration........................................................................................................................................ 900
Displaying the Status of Stacking Ports............................................................................................................... 900
Removing a Unit from a Stack......................................................................................................................................901
Troubleshoot a Stack.....................................................................................................................................................903
Recover from Stack Link Flaps.............................................................................................................................. 903
Recover from a Card Problem State on a Stack..................................................................................................903
53 Storm Control..........................................................................................................................................905
Congure Storm Control.............................................................................................................................................. 905
Conguring Storm Control from INTERFACE Mode.......................................................................................... 905
Conguring Storm Control from CONFIGURATION Mode................................................................................906
54 Spanning Tree Protocol (STP)................................................................................................................. 907
Protocol Overview......................................................................................................................................................... 907
Congure Spanning Tree.............................................................................................................................................. 908
Related Conguration Tasks...................................................................................................................................908
Important Points to Remember................................................................................................................................... 908
Conguring Interfaces for Layer 2 Mode................................................................................................................... 909
Enabling Spanning Tree Protocol Globally................................................................................................................... 910
Adding an Interface to the Spanning Tree Group.......................................................................................................912
Modifying Global Parameters........................................................................................................................................912
Modifying Interface STP Parameters...........................................................................................................................913
Enabling PortFast........................................................................................................................................................... 913
Prevent Network Disruptions with BPDU Guard..................................................................................................914
Selecting STP Root........................................................................................................................................................915
STP Root Guard............................................................................................................................................................. 916
Root Guard Scenario................................................................................................................................................916
Conguring Root Guard...........................................................................................................................................917
Enabling SNMP Traps for Root Elections and Topology Changes........................................................................... 918
Conguring Spanning Trees as Hitless.........................................................................................................................918
STP Loop Guard............................................................................................................................................................. 918
Conguring Loop Guard.......................................................................................................................................... 919
Displaying STP Guard Conguration........................................................................................................................... 920
55 SupportAssist...........................................................................................................................................921
Conguring SupportAssist Using a Conguration Wizard........................................................................................922
Conguring SupportAssist Manually........................................................................................................................... 922
Conguring SupportAssist Activity..............................................................................................................................924
Conguring SupportAssist Company..........................................................................................................................925
Conguring SupportAssist Person.............................................................................................................................. 926
Conguring SupportAssist Server...............................................................................................................................926
Viewing SupportAssist Conguration..........................................................................................................................927
56 System Time and Date.............................................................................................................................929
Network Time Protocol.................................................................................................................................................929
Protocol Overview...................................................................................................................................................930
Contents
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