Specifications

Contents
vi
Cisco MWR 2941 Mobile Wireless Edge Router Release 3.5 Software Configuration Guide, Cisco IOS Release 15.1(3)MR
OL-26895-01
CHAPTER 9 Configuring STP 9-1
Understanding Spanning-Tree Features 9-1
STP Overview 9-2
Spanning-Tree Topology and BPDUs 9-2
Bridge ID, Switch Priority, and Extended System ID 9-3
Spanning-Tree Interface States 9-4
Blocking State 9-5
Listening State 9-6
Learning State 9-6
Forwarding State 9-6
Disabled State 9-6
How a Switch or Port Becomes the Root Switch or Root Port 9-7
Spanning Tree and Redundant Connectivity 9-7
Spanning-Tree Address Management 9-8
Accelerated Aging to Retain Connectivity 9-8
Spanning-Tree Modes and Protocols 9-9
Supported Spanning-Tree Instances 9-10
Spanning-Tree Interoperability and Backward Compatibility 9-10
STP and IEEE 802.1Q Trunks 9-10
Configuring Spanning-Tree Features 9-10
Default Spanning-Tree Configuration 9-11
Spanning-Tree Configuration Guidelines 9-11
Enabling Spanning Tree on an ENI 9-12
Changing the Spanning-Tree Mode 9-13
Disabling Spanning Tree 9-14
Configuring the Router as a Root Switch 9-14
Configuring a Secondary Root Switch 9-16
Configuring Port Priority 9-16
Configuring Path Cost 9-18
Configuring the Switch Priority of a VLAN 9-19
Configuring Spanning-Tree Timers 9-20
Configuring the Hello Time 9-20
Configuring the Forwarding-Delay Time for a VLAN 9-21
Configuring the Maximum-Aging Time for a VLAN 9-21
Displaying the Spanning-Tree Status 9-22
CHAPTER 10 Configuring MSTP 10-1
Understanding MSTP 10-2
Multiple Spanning-Tree Regions 10-2