Users Guide

Congure Storm Control...............................................................................................................................................964
Conguring Storm Control from INTERFACE Mode...........................................................................................964
Conguring Storm Control from CONFIGURATION Mode................................................................................965
54 Spanning Tree Protocol (STP)................................................................................................................. 966
Protocol Overview.........................................................................................................................................................966
Congure Spanning Tree.............................................................................................................................................. 966
Related Conguration Tasks................................................................................................................................... 967
Important Points to Remember....................................................................................................................................967
Conguring Interfaces for Layer 2 Mode....................................................................................................................968
Enabling Spanning Tree Protocol Globally.................................................................................................................. 969
Adding an Interface to the Spanning Tree Group....................................................................................................... 971
Modifying Global Parameters........................................................................................................................................ 971
Modifying Interface STP Parameters.......................................................................................................................... 972
Enabling PortFast...........................................................................................................................................................972
Preventing Network Disruptions with BPDU Guard..................................................................................................973
Selecting STP Root....................................................................................................................................................... 975
STP Root Guard.............................................................................................................................................................975
Root Guard Scenario............................................................................................................................................... 975
Conguring Root Guard.......................................................................................................................................... 976
Enabling SNMP Traps for Root Elections and Topology Changes........................................................................... 977
STP Loop Guard.............................................................................................................................................................977
Conguring Loop Guard..........................................................................................................................................978
Displaying STP Guard Conguration............................................................................................................................979
55 SupportAssist..........................................................................................................................................980
Conguring SupportAssist Using a Conguration Wizard.........................................................................................981
Conguring SupportAssist Manually............................................................................................................................981
Conguring SupportAssist Activity............................................................................................................................. 983
Conguring SupportAssist Company..........................................................................................................................984
Conguring SupportAssist Person.............................................................................................................................. 985
Conguring SupportAssist Server...............................................................................................................................986
Viewing SupportAssist Conguration......................................................................................................................... 986
56 System Time and Date.............................................................................................................................989
Network Time Protocol.................................................................................................................................................989
Protocol Overview...................................................................................................................................................990
Congure the Network Time Protocol..................................................................................................................990
Enabling NTP............................................................................................................................................................ 991
Conguring NTP Broadcasts.................................................................................................................................. 991
Disabling NTP on an Interface................................................................................................................................ 991
Conguring a Source IP Address for NTP Packets............................................................................................. 992
Conguring NTP Authentication............................................................................................................................992
Time and Date................................................................................................................................................................994
Conguration Task List ...........................................................................................................................................994
Setting the Time and Date for the Switch Software Clock............................................................................... 995
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