Administrator Guide

Troubleshoot a Stack.....................................................................................................................................................916
Recover from Stack Link Flaps...............................................................................................................................917
Recover from a Card Problem State on a Stack..................................................................................................917
53 Storm Control.......................................................................................................................................... 919
Configure Storm Control...............................................................................................................................................919
Configuring Storm Control from INTERFACE Mode...........................................................................................919
Configuring Storm Control from CONFIGURATION Mode............................................................................... 920
54 Spanning Tree Protocol (STP).................................................................................................................921
Protocol Overview......................................................................................................................................................... 921
Configure Spanning Tree..............................................................................................................................................922
Related Configuration Tasks.................................................................................................................................. 922
Important Points to Remember...................................................................................................................................922
Configuring Interfaces for Layer 2 Mode................................................................................................................... 923
Enabling Spanning Tree Protocol Globally..................................................................................................................924
Adding an Interface to the Spanning Tree Group..................................................................................................... 926
Modifying Global Parameters.......................................................................................................................................926
Modifying Interface STP Parameters..........................................................................................................................927
Enabling PortFast.......................................................................................................................................................... 927
Prevent Network Disruptions with BPDU Guard................................................................................................ 928
Selecting STP Root.......................................................................................................................................................930
STP Root Guard............................................................................................................................................................ 930
Root Guard Scenario...............................................................................................................................................930
Configuring Root Guard.......................................................................................................................................... 931
Enabling SNMP Traps for Root Elections and Topology Changes......................................................................... 932
Configuring Spanning Trees as Hitless....................................................................................................................... 932
STP Loop Guard............................................................................................................................................................ 932
Configuring Loop Guard..........................................................................................................................................934
Displaying STP Guard Configuration...........................................................................................................................934
55 SupportAssist..........................................................................................................................................936
Configuring SupportAssist Using a Configuration Wizard........................................................................................937
Configuring SupportAssist Manually........................................................................................................................... 937
Configuring SupportAssist Activity............................................................................................................................. 939
Configuring SupportAssist Company..........................................................................................................................940
Configuring SupportAssist Person...............................................................................................................................941
Configuring SupportAssist Server................................................................................................................................941
Viewing SupportAssist Configuration......................................................................................................................... 942
56 System Time and Date.............................................................................................................................944
Network Time Protocol.................................................................................................................................................944
Protocol Overview...................................................................................................................................................945
Configure the Network Time Protocol................................................................................................................. 945
Enabling NTP........................................................................................................................................................... 946
Configuring NTP Broadcasts................................................................................................................................. 946
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