Users Guide

Troubleshoot a Stack.....................................................................................................................................................830
Recover from Stack Link Flaps.............................................................................................................................. 830
Recover from a Card Problem State on a Stack..................................................................................................830
51 Storm Control...........................................................................................................................................832
Congure Storm Control...............................................................................................................................................832
Conguring Storm Control from INTERFACE Mode...........................................................................................832
Conguring Storm Control from CONFIGURATION Mode................................................................................833
52 Spanning Tree Protocol (STP)................................................................................................................. 834
Protocol Overview......................................................................................................................................................... 834
Congure Spanning Tree.............................................................................................................................................. 835
Related Conguration Tasks...................................................................................................................................835
Important Points to Remember................................................................................................................................... 835
Conguring Interfaces for Layer 2 Mode....................................................................................................................836
Enabling Spanning Tree Protocol Globally...................................................................................................................837
Adding an Interface to the Spanning Tree Group...................................................................................................... 839
Modifying Global Parameters....................................................................................................................................... 839
Modifying Interface STP Parameters..........................................................................................................................840
Enabling PortFast.......................................................................................................................................................... 840
Prevent Network Disruptions with BPDU Guard..................................................................................................841
Selecting STP Root....................................................................................................................................................... 842
STP Root Guard.............................................................................................................................................................843
Root Guard Scenario............................................................................................................................................... 843
Conguring Root Guard..........................................................................................................................................844
Enabling SNMP Traps for Root Elections and Topology Changes...........................................................................845
Conguring Spanning Trees as Hitless........................................................................................................................845
STP Loop Guard............................................................................................................................................................ 845
Conguring Loop Guard..........................................................................................................................................846
Displaying STP Guard Conguration............................................................................................................................847
53 SupportAssist.......................................................................................................................................... 848
Conguring SupportAssist Using a Conguration Wizard........................................................................................849
Conguring SupportAssist Manually........................................................................................................................... 849
Conguring SupportAssist Activity.............................................................................................................................. 851
Conguring SupportAssist Company..........................................................................................................................852
Conguring SupportAssist Person.............................................................................................................................. 853
Conguring SupportAssist Server...............................................................................................................................853
Viewing SupportAssist Conguration......................................................................................................................... 854
54 System Time and Date.............................................................................................................................856
Network Time Protocol.................................................................................................................................................856
Protocol Overview................................................................................................................................................... 857
Congure the Network Time Protocol.................................................................................................................. 857
Enabling NTP........................................................................................................................................................... 858
Conguring NTP Broadcasts................................................................................................................................. 858
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