Concept Guide

Split a Stack............................................................................................................................................................. 994
Stacking Conguration Tasks.......................................................................................................................................994
Assigning Unit Numbers to Units in an Stack...................................................................................................... 995
Creating a Virtual Stack Unit on a Stack.............................................................................................................. 995
Displaying Information about a Stack....................................................................................................................995
Inuencing Management Unit Selection on a Stack........................................................................................... 998
Managing Redundancy on a Stack........................................................................................................................998
Resetting a Unit on a Stack....................................................................................................................................999
Enabling Mixed-mode Stacking............................................................................................................................. 999
Verify a Stack Conguration.......................................................................................................................................1000
Displaying the Status of Stacking Ports..............................................................................................................1000
Remove Units or Front End Ports from a Stack....................................................................................................... 1001
Removing a Unit from a Stack.............................................................................................................................. 1001
Removing Front End Port Stacking..................................................................................................................... 1002
Troubleshoot a Stack................................................................................................................................................... 1003
Recover from Stack Link Flaps.............................................................................................................................1003
Recover from a Card Problem State on a Stack................................................................................................1003
54 Storm Control........................................................................................................................................ 1005
Congure Storm Control.............................................................................................................................................1005
Conguring Storm Control from INTERFACE Mode.........................................................................................1005
Conguring Storm Control from CONFIGURATION Mode.............................................................................. 1006
55 Spanning Tree Protocol (STP)................................................................................................................1007
Protocol Overview........................................................................................................................................................1007
Congure Spanning Tree.............................................................................................................................................1008
Related Conguration Tasks................................................................................................................................. 1008
Important Points to Remember..................................................................................................................................1008
Conguring Interfaces for Layer 2 Mode..................................................................................................................1009
Enabling Spanning Tree Protocol Globally..................................................................................................................1010
Adding an Interface to the Spanning Tree Group......................................................................................................1012
Modifying Global Parameters...................................................................................................................................... 1012
Modifying Interface STP Parameters......................................................................................................................... 1013
Enabling PortFast..........................................................................................................................................................1013
Prevent Network Disruptions with BPDU Guard................................................................................................ 1014
Selecting STP Root...................................................................................................................................................... 1016
STP Root Guard............................................................................................................................................................1016
Root Guard Scenario.............................................................................................................................................. 1016
Conguring Root Guard......................................................................................................................................... 1017
Enabling SNMP Traps for Root Elections and Topology Changes..........................................................................1018
Conguring Spanning Trees as Hitless....................................................................................................................... 1018
STP Loop Guard............................................................................................................................................................1018
Conguring Loop Guard........................................................................................................................................ 1020
Displaying STP Guard Conguration..........................................................................................................................1020
56 SupportAssist.........................................................................................................................................1022
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