Concept Guide

Assigning Unit Numbers to Units in an Stack...................................................................................................... 989
Creating a Virtual Stack Unit on a Stack.............................................................................................................. 989
Displaying Information about a Stack....................................................................................................................989
Inuencing Management Unit Selection on a Stack........................................................................................... 992
Managing Redundancy on a Stack........................................................................................................................993
Resetting a Unit on a Stack....................................................................................................................................993
Verify a Stack Conguration........................................................................................................................................ 993
Displaying the Status of Stacking Ports............................................................................................................... 994
Remove Units or Front End Ports from a Stack........................................................................................................995
Removing a Unit from a Stack...............................................................................................................................995
Removing Front End Port Stacking.......................................................................................................................996
Troubleshoot a Stack.....................................................................................................................................................996
Recover from Stack Link Flaps.............................................................................................................................. 997
Recover from a Card Problem State on a Stack..................................................................................................997
55 Storm Control..........................................................................................................................................999
Congure Storm Control.............................................................................................................................................. 999
Conguring Storm Control from INTERFACE Mode...........................................................................................999
Conguring Storm Control from CONFIGURATION Mode.............................................................................. 1000
56 Spanning Tree Protocol (STP)................................................................................................................ 1001
Protocol Overview........................................................................................................................................................ 1001
Congure Spanning Tree.............................................................................................................................................1002
Related Conguration Tasks................................................................................................................................. 1002
Important Points to Remember..................................................................................................................................1002
Conguring Interfaces for Layer 2 Mode..................................................................................................................1003
Enabling Spanning Tree Protocol Globally.................................................................................................................1004
Adding an Interface to the Spanning Tree Group.....................................................................................................1006
Modifying Global Parameters..................................................................................................................................... 1006
Modifying Interface STP Parameters.........................................................................................................................1007
Enabling PortFast.........................................................................................................................................................1007
Prevent Network Disruptions with BPDU Guard............................................................................................... 1008
Selecting STP Root...................................................................................................................................................... 1010
STP Root Guard............................................................................................................................................................1010
Root Guard Scenario.............................................................................................................................................. 1010
Conguring Root Guard..........................................................................................................................................1011
Enabling SNMP Traps for Root Elections and Topology Changes..........................................................................1012
Conguring Spanning Trees as Hitless....................................................................................................................... 1012
STP Loop Guard............................................................................................................................................................1012
Conguring Loop Guard......................................................................................................................................... 1014
Displaying STP Guard Conguration...........................................................................................................................1014
57 SupportAssist......................................................................................................................................... 1016
Conguring SupportAssist Using a Conguration Wizard....................................................................................... 1017
Conguring SupportAssist Manually...........................................................................................................................1017
Conguring SupportAssist Activity.............................................................................................................................1019
Contents
31