Concept Guide

Table Of Contents
Accessing the CLI..................................................................................................................................................... 811
Conguring and Bringing Up a Stack......................................................................................................................811
Adding a Stack Unit..................................................................................................................................................812
Resetting a Unit on a Stack.....................................................................................................................................813
Removing an Aggregator from a Stack..................................................................................................................813
Merging Two Operational Stacks............................................................................................................................813
Verifying a Stack Conguration.................................................................................................................................... 814
Using Show Commands.......................................................................................................................................... 814
Troubleshooting a Switch Stack................................................................................................................................... 814
Failure Scenarios.......................................................................................................................................................815
Upgrading a Switch Stack............................................................................................................................................. 817
Upgrading a Single Stack Unit...................................................................................................................................... 818
Stack Link Failure Detection..........................................................................................................................................818
Conguring Port Shutdown when Both Stack Links are Down.........................................................................820
54 Storm Control...........................................................................................................................................821
Congure Storm Control............................................................................................................................................... 821
Conguring Storm Control from INTERFACE Mode............................................................................................821
Conguring Storm Control from CONFIGURATION Mode................................................................................ 822
55 Broadcast Storm Control......................................................................................................................... 823
Supported Modes..........................................................................................................................................................823
Disabling Broadcast Storm Control..............................................................................................................................823
Displaying Broadcast-Storm Control Status...............................................................................................................823
Conguring Storm Control............................................................................................................................................823
56 Spanning Tree Protocol (STP)................................................................................................................. 824
Protocol Overview......................................................................................................................................................... 824
Congure Spanning Tree...............................................................................................................................................824
Related Conguration Tasks...................................................................................................................................825
Important Points to Remember............................................................................................................................. 825
Conguring Interfaces for Layer 2 Mode....................................................................................................................826
Enabling Spanning Tree Protocol Globally...................................................................................................................827
Adding an Interface to the Spanning Tree Group...................................................................................................... 829
Removing an Interface from the Spanning Tree Group............................................................................................ 829
Modifying Global Parameters....................................................................................................................................... 829
Modifying Interface STP Parameters..........................................................................................................................830
Enabling Port Fast......................................................................................................................................................... 830
Prevent Network Disruptions with BPDU Guard..................................................................................................831
Global BPDU Filtering....................................................................................................................................................833
Interface BPDU Filtering.........................................................................................................................................833
Selecting STP Root....................................................................................................................................................... 834
STP Root Guard.............................................................................................................................................................835
Root Guard Scenario...............................................................................................................................................835
Conguring Root Guard..........................................................................................................................................836
SNMP Traps for Root Elections and Topology Changes...........................................................................................837
Contents
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