Users Guide

Recover from Stack Link Flaps.................................................................................................................................828
Recover from a Card Problem State on a Stack....................................................................................................... 829
53 Storm Control........................................................................................................... 830
Congure Storm Control................................................................................................................................................ 830
Conguring Storm Control from INTERFACE Mode.................................................................................................830
Conguring Storm Control from CONFIGURATION Mode........................................................................................831
54 Spanning Tree Protocol (STP)...................................................................................832
Protocol Overview......................................................................................................................................................... 832
Congure Spanning Tree................................................................................................................................................ 832
Related Conguration Tasks..................................................................................................................................... 832
Important Points to Remember......................................................................................................................................832
Conguring Interfaces for Layer 2 Mode........................................................................................................................833
Enabling Spanning Tree Protocol Globally.......................................................................................................................834
Adding an Interface to the Spanning Tree Group............................................................................................................836
Modifying Global Parameters......................................................................................................................................... 836
Modifying Interface STP Parameters..............................................................................................................................837
Enabling PortFast...........................................................................................................................................................837
Prevent Network Disruptions with BPDU Guard...................................................................................................... 838
Selecting STP Root........................................................................................................................................................840
STP Root Guard.............................................................................................................................................................840
Root Guard Scenario................................................................................................................................................840
Conguring Root Guard............................................................................................................................................ 841
Enabling SNMP Traps for Root Elections and Topology Changes................................................................................... 842
Conguring Spanning Trees as Hitless............................................................................................................................842
STP Loop Guard.............................................................................................................................................................842
Conguring Loop Guard........................................................................................................................................... 843
Displaying STP Guard Conguration...............................................................................................................................844
55 SupportAssist........................................................................................................... 845
Conguring SupportAssist Using a Conguration Wizard...............................................................................................845
Conguring SupportAssist Manually...............................................................................................................................846
Conguring SupportAssist Activity.................................................................................................................................847
Conguring SupportAssist Company..............................................................................................................................849
Conguring SupportAssist Person................................................................................................................................. 849
Conguring SupportAssist Server..................................................................................................................................850
Viewing SupportAssist Conguration..............................................................................................................................851
56 System Time and Date.............................................................................................. 853
Network Time Protocol..................................................................................................................................................853
Protocol Overview................................................................................................................................................... 854
Congure the Network Time Protocol......................................................................................................................854
Enabling NTP........................................................................................................................................................... 854
Conguring NTP Broadcasts....................................................................................................................................855
Disabling NTP on an Interface..................................................................................................................................855
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