Users Guide

Congure Storm Control...............................................................................................................................................987
Conguring Storm Control from INTERFACE Mode...........................................................................................987
Conguring Storm Control from CONFIGURATION Mode................................................................................988
56 Spanning Tree Protocol (STP)................................................................................................................. 989
Protocol Overview.........................................................................................................................................................989
Congure Spanning Tree.............................................................................................................................................. 990
Related Conguration Tasks...................................................................................................................................990
Important Points to Remember................................................................................................................................... 990
Conguring Interfaces for Layer 2 Mode.................................................................................................................... 991
Enabling Spanning Tree Protocol Globally...................................................................................................................992
Adding an Interface to the Spanning Tree Group...................................................................................................... 994
Modifying Global Parameters.......................................................................................................................................994
Modifying Interface STP Parameters..........................................................................................................................995
Enabling PortFast.......................................................................................................................................................... 995
Prevent Network Disruptions with BPDU Guard.................................................................................................996
Selecting STP Root....................................................................................................................................................... 998
STP Root Guard.............................................................................................................................................................998
Root Guard Scenario...............................................................................................................................................998
Conguring Root Guard..........................................................................................................................................999
Enabling SNMP Traps for Root Elections and Topology Changes.........................................................................1000
Conguring Spanning Trees as Hitless...................................................................................................................... 1000
STP Loop Guard...........................................................................................................................................................1000
Conguring Loop Guard........................................................................................................................................ 1002
Displaying STP Guard Conguration..........................................................................................................................1002
57 SupportAssist.........................................................................................................................................1004
Conguring SupportAssist Using a Conguration Wizard...................................................................................... 1005
Conguring SupportAssist Manually......................................................................................................................... 1005
Conguring SupportAssist Activity............................................................................................................................ 1007
Conguring SupportAssist Company........................................................................................................................ 1008
Conguring SupportAssist Person.............................................................................................................................1009
Conguring SupportAssist Server............................................................................................................................. 1009
Viewing SupportAssist Conguration.........................................................................................................................1010
58 System Time and Date............................................................................................................................ 1012
Network Time Protocol................................................................................................................................................ 1012
Protocol Overview.................................................................................................................................................. 1013
Congure the Network Time Protocol................................................................................................................. 1013
Enabling NTP...........................................................................................................................................................1014
Conguring NTP Broadcasts.................................................................................................................................1014
Disabling NTP on an Interface...............................................................................................................................1015
Conguring a Source IP Address for NTP Packets............................................................................................ 1015
Conguring NTP Authentication...........................................................................................................................1015
Conguring NTP control key password............................................................................................................... 1018
Conguring a Custom-dened Period for NTP time Synchronization............................................................. 1018
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