Concept Guide

Remove Units or Front End Ports from a Stack........................................................................................................905
Removing a Unit from a Stack...............................................................................................................................905
Removing Front End Port Stacking.......................................................................................................................906
Troubleshoot a Stack.....................................................................................................................................................906
Recover from Stack Link Flaps.............................................................................................................................. 907
Recover from a Card Problem State on a Stack..................................................................................................907
50 Storm Control..........................................................................................................................................909
Congure Storm Control.............................................................................................................................................. 909
Conguring Storm Control from INTERFACE Mode...........................................................................................909
Conguring Storm Control from CONFIGURATION Mode.................................................................................910
51 Spanning Tree Protocol (STP)................................................................................................................... 911
Protocol Overview.......................................................................................................................................................... 911
Congure Spanning Tree............................................................................................................................................... 912
Related Conguration Tasks....................................................................................................................................912
Important Points to Remember.................................................................................................................................... 912
Conguring Interfaces for Layer 2 Mode.................................................................................................................... 913
Enabling Spanning Tree Protocol Globally................................................................................................................... 914
Adding an Interface to the Spanning Tree Group.......................................................................................................916
Modifying Global Parameters........................................................................................................................................916
Modifying Interface STP Parameters...........................................................................................................................917
Enabling PortFast........................................................................................................................................................... 917
Prevent Network Disruptions with BPDU Guard................................................................................................. 918
Selecting STP Root....................................................................................................................................................... 920
STP Root Guard.............................................................................................................................................................920
Root Guard Scenario............................................................................................................................................... 920
Conguring Root Guard...........................................................................................................................................921
Enabling SNMP Traps for Root Elections and Topology Changes...........................................................................922
Conguring Spanning Trees as Hitless........................................................................................................................922
STP Loop Guard.............................................................................................................................................................922
Conguring Loop Guard..........................................................................................................................................924
Displaying STP Guard Conguration........................................................................................................................... 924
52 SupportAssist.......................................................................................................................................... 926
Conguring SupportAssist Using a Conguration Wizard........................................................................................ 927
Conguring SupportAssist Manually........................................................................................................................... 927
Conguring SupportAssist Activity............................................................................................................................. 929
Conguring SupportAssist Company..........................................................................................................................930
Conguring SupportAssist Person............................................................................................................................... 931
Conguring SupportAssist Server................................................................................................................................931
Viewing SupportAssist Conguration..........................................................................................................................932
53 System Time and Date.............................................................................................................................934
Network Time Protocol.................................................................................................................................................934
Protocol Overview...................................................................................................................................................935
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