Users Guide

Failure Scenarios...................................................................................................................................................... 835
Upgrading a Switch Stack........................................................................................................................................838
Upgrading a Single Stack Unit..................................................................................................................................839
57 Storm Control........................................................................................................... 840
Congure Storm Control................................................................................................................................................ 840
Conguring Storm Control from INTERFACE Mode.................................................................................................840
Conguring Storm Control from CONFIGURATION Mode.......................................................................................840
58 Spanning Tree Protocol (STP)................................................................................... 841
Protocol Overview.......................................................................................................................................................... 841
Congure Spanning Tree.................................................................................................................................................841
Related Conguration Tasks......................................................................................................................................841
Important Points to Remember.................................................................................................................................841
Conguring Interfaces for Layer 2 Mode........................................................................................................................842
Enabling Spanning Tree Protocol Globally.......................................................................................................................843
Adding an Interface to the Spanning Tree Group............................................................................................................845
Removing an Interface from the Spanning Tree Group...................................................................................................845
Modifying Global Parameters......................................................................................................................................... 845
Modifying Interface STP Parameters............................................................................................................................. 846
Enabling PortFast...........................................................................................................................................................846
Prevent Network Disruptions with BPDU Guard............................................................................................................ 847
Global BPDU Filtering.....................................................................................................................................................849
Interface BPDU Filtering................................................................................................................................................ 849
Selecting STP Root........................................................................................................................................................850
STP Root Guard.............................................................................................................................................................850
Root Guard Scenario.................................................................................................................................................851
Conguring Root Guard........................................................................................................................................... 852
Enabling SNMP Traps for Root Elections and Topology Changes...................................................................................852
Conguring Spanning Trees as Hitless............................................................................................................................852
STP Loop Guard.............................................................................................................................................................853
Conguring Loop Guard........................................................................................................................................... 854
Displaying STP Guard Conguration...............................................................................................................................855
59 System Time and Date.............................................................................................. 856
Network Time Protocol..................................................................................................................................................856
Protocol Overview....................................................................................................................................................857
Congure the Network Time Protocol......................................................................................................................857
Enabling NTP........................................................................................................................................................... 857
Conguring NTP Broadcasts....................................................................................................................................858
Disabling NTP on an Interface..................................................................................................................................858
Conguring a Source IP Address for NTP Packets...................................................................................................858
Conguring NTP Authentication.............................................................................................................................. 859
Dell Networking OS Time and Date.................................................................................................................................861
Conguration Task List .............................................................................................................................................861
Setting the Time and Date for the Switch Software Clock.......................................................................................862
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