Contents
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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Spanning-Tree Topology and BPDUs 20-3
Bridge ID, Switch Priority, and Extended System ID 20-4
Spanning-Tree Interface States 20-5
Blocking State 20-6
Listening State 20-7
Learning State 20-7
Forwarding State 20-7
Disabled State 20-7
How a Switch or Port Becomes the Root Switch or Root Port 20-8
Spanning Tree and Redundant Connectivity 20-8
Spanning-Tree Address Management 20-8
Accelerated Aging to Retain Connectivity 20-9
Spanning-Tree Modes and Protocols 20-9
Supported Spanning-Tree Instances 20-10
Spanning-Tree Interoperability and Backward Compatibility 20-10
STP and IEEE 802.1Q Trunks 20-10
VLAN-Bridge Spanning Tree 20-11
Spanning Tree and Switch Stacks 20-11
Configuring Spanning-Tree Features 20-12
Default Spanning-Tree Configuration 20-12
Spanning-Tree Configuration Guidelines 20-13
Changing the Spanning-Tree Mode. 20-14
Disabling Spanning Tree 20-15
Configuring the Root Switch 20-15
Configuring a Secondary Root Switch 20-17
Configuring Port Priority 20-18
Configuring Path Cost 20-20
Configuring the Switch Priority of a VLAN 20-21
Configuring Spanning-Tree Timers 20-22
Configuring the Hello Time 20-22
Configuring the Forwarding-Delay Time for a VLAN 20-23
Configuring the Maximum-Aging Time for a VLAN 20-23
Configuring the Transmit Hold-Count 20-24
Displaying the Spanning-Tree Status 20-24