White Papers

Recover from Stack Link Flaps.............................................................................................................................. 936
Recover from a Card Problem State on a Stack..................................................................................................936
52 Storm Control.......................................................................................................................................... 938
Congure Storm Control...............................................................................................................................................938
Conguring Storm Control from INTERFACE Mode...........................................................................................938
Conguring Storm Control from CONFIGURATION Mode................................................................................939
53 Spanning Tree Protocol (STP)................................................................................................................. 940
Protocol Overview.........................................................................................................................................................940
Congure Spanning Tree............................................................................................................................................... 941
Related Conguration Tasks....................................................................................................................................941
Important Points to Remember.................................................................................................................................... 941
Conguring Interfaces for Layer 2 Mode....................................................................................................................942
Enabling Spanning Tree Protocol Globally...................................................................................................................943
Adding an Interface to the Spanning Tree Group...................................................................................................... 945
Modifying Global Parameters....................................................................................................................................... 945
Modifying Interface STP Parameters..........................................................................................................................946
Enabling PortFast.......................................................................................................................................................... 946
Prevent Network Disruptions with BPDU Guard.................................................................................................947
Selecting STP Root....................................................................................................................................................... 949
STP Root Guard.............................................................................................................................................................949
Root Guard Scenario...............................................................................................................................................949
Conguring Root Guard..........................................................................................................................................950
Enabling SNMP Traps for Root Elections and Topology Changes........................................................................... 951
Conguring Spanning Trees as Hitless.........................................................................................................................951
STP Loop Guard............................................................................................................................................................. 951
Conguring Loop Guard..........................................................................................................................................953
Displaying STP Guard Conguration........................................................................................................................... 953
54 SupportAssist..........................................................................................................................................955
Conguring SupportAssist Using a Conguration Wizard........................................................................................956
Conguring SupportAssist Manually...........................................................................................................................956
Conguring SupportAssist Activity............................................................................................................................. 958
Conguring SupportAssist Company..........................................................................................................................959
Conguring SupportAssist Person.............................................................................................................................. 960
Conguring SupportAssist Server...............................................................................................................................960
Viewing SupportAssist Conguration.......................................................................................................................... 961
55 System Time and Date.............................................................................................................................963
Network Time Protocol.................................................................................................................................................963
Protocol Overview...................................................................................................................................................964
Congure the Network Time Protocol..................................................................................................................964
Enabling NTP........................................................................................................................................................... 965
Conguring NTP Broadcasts................................................................................................................................. 965
Disabling NTP on an Interface............................................................................................................................... 966
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