Contents
xxi
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
CHAPTER
21 Configuring MSTP 21-1
Understanding MSTP 21-2
Multiple Spanning-Tree Regions 21-2
IST, CIST, and CST 21-2
Operations Within an MST Region 21-3
Operations Between MST Regions 21-3
IEEE 802.1s Terminology 21-5
Hop Count 21-5
Boundary Ports 21-6
IEEE 802.1s Implementation 21-6
Port Role Naming Change 21-6
Interoperation Between Legacy and Standard Switches 21-7
Detecting Unidirectional Link Failure 21-7
MSTP and Switch Stacks 21-8
Interoperability with IEEE 802.1D STP 21-8
Understanding RSTP 21-9
Port Roles and the Active Topology 21-9
Rapid Convergence 21-10
Synchronization of Port Roles 21-11
Bridge Protocol Data Unit Format and Processing 21-12
Processing Superior BPDU Information 21-13
Processing Inferior BPDU Information 21-13
Topology Changes 21-13
Configuring MSTP Features 21-14
Default MSTP Configuration 21-14
MSTP Configuration Guidelines 21-15
Specifying the MST Region Configuration and Enabling MSTP 21-16
Configuring the Root Switch 21-18
Configuring a Secondary Root Switch 21-19
Configuring Port Priority 21-20
Configuring Path Cost 21-21
Configuring the Switch Priority 21-22
Configuring the Hello Time 21-23
Configuring the Forwarding-Delay Time 21-24
Configuring the Maximum-Aging Time 21-24
Configuring the Maximum-Hop Count 21-25
Specifying the Link Type to Ensure Rapid Transitions 21-25
Designating the Neighbor Type 21-26
Restarting the Protocol Migration Process 21-26
Displaying the MST Configuration and Status 21-27