Administrator Guide

Recover from Stack Link Flaps..................................................................................................................................884
Recover from a Card Problem State on a Stack.....................................................................................................884
55 Storm Control........................................................................................................................ 886
Configure Storm Control..................................................................................................................................................886
Configuring Storm Control from INTERFACE Mode..............................................................................................886
Configuring Storm Control from CONFIGURATION Mode................................................................................... 887
56 Spanning Tree Protocol (STP)................................................................................................. 888
Protocol Overview............................................................................................................................................................ 888
Configure Spanning Tree................................................................................................................................................. 888
Important Points to Remember.......................................................................................................................................889
Configuring Interfaces for Layer 2 Mode.......................................................................................................................889
Enabling Spanning Tree Protocol Globally..................................................................................................................... 890
Adding an Interface to the Spanning Tree Group.........................................................................................................892
Modifying Global Parameters.......................................................................................................................................... 892
Modifying Interface STP Parameters.............................................................................................................................893
Enabling PortFast..............................................................................................................................................................893
Prevent Network Disruptions with BPDU Guard.................................................................................................... 894
Selecting STP Root...........................................................................................................................................................896
STP Root Guard................................................................................................................................................................896
Root Guard Scenario...................................................................................................................................................896
Configuring Root Guard..............................................................................................................................................897
Enabling SNMP Traps for Root Elections and Topology Changes.............................................................................898
Configuring Spanning Trees as Hitless...........................................................................................................................898
STP Loop Guard................................................................................................................................................................898
Configuring Loop Guard............................................................................................................................................. 899
Displaying STP Guard Configuration.............................................................................................................................. 900
57 SupportAssist......................................................................................................................... 901
Configuring SupportAssist Using a Configuration Wizard............................................................................................901
Configuring SupportAssist Manually...............................................................................................................................902
Configuring SupportAssist Activity.................................................................................................................................903
Configuring SupportAssist Company............................................................................................................................. 905
Configuring SupportAssist Person..................................................................................................................................905
Configuring SupportAssist Server.................................................................................................................................. 906
Viewing SupportAssist Configuration............................................................................................................................. 907
58 System Time and Date............................................................................................................ 909
Network Time Protocol....................................................................................................................................................909
Protocol Overview....................................................................................................................................................... 910
Configure the Network Time Protocol......................................................................................................................910
Enabling NTP................................................................................................................................................................910
Configuring NTP Broadcasts.......................................................................................................................................911
Disabling NTP on an Interface.....................................................................................................................................911
Configuring a Source IP Address for NTP Packets..................................................................................................911
Configuring NTP Authentication................................................................................................................................912
Configuring NTP control key password.................................................................................................................... 914
Configuring the NTP Step-Threshold....................................................................................................................... 914
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