Name: Cisco 2950 - Catalyst Switch
Brand: Cisco
Rating: 4 (1 reviews)

To Next Page

To Previous Page

15-11

Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide

78-11380-10

Chapter 15 Configuring MSTP

Configuring MSTP Features

• Propagation—When an RSTP switch receives a TC message from another switch through a

designated or root port, it propagates the change to all of its nonedge, designated ports and to the

root port (excluding the port on which it is received). The switch starts the TC-while timer for all

such ports and flushes the information learned on them.

• Protocol migration—For backward compatibility with 802.1D switches, RSTP selectively sends

802.1D configuration BPDUs and TCN BPDUs on a per-port basis.

When a port is initialized, the migrate-delay timer is started (specifies the minimum time during

which RSTP BPDUs are sent), and RSTP BPDUs are sent. While this timer is active, the switch

processes all BPDUs received on that port and ignores the protocol type.

If the switch receives an 802.1D BPDU after the port’s migration-delay timer has expired, it assumes

that it is connected to an 802.1D switch and starts using only 802.1D BPDUs. However, if the RSTP

switch is using 802.1D BPDUs on a port and receives an RSTP BPDU after the timer has expired,

it restarts the timer and starts using RSTP BPDUs on that port.

Configuring MSTP Features

These sections describe how to configure basic MSTP features:

• Default MSTP Configuration, page 15-12

• MSTP Configuration Guidelines, page 15-12

• Specifying the MST Region Configuration and Enabling MSTP, page 15-13 (required)

• Configuring the Root Switch, page 15-14 (optional)

• Configuring a Secondary Root Switch, page 15-16 (optional)

• Configuring the Port Priority, page 15-17 (optional)

• Configuring the Path Cost, page 15-18 (optional)

• Configuring the Switch Priority, page 15-19 (optional)

• Configuring the Hello Time, page 15-19 (optional)

• Configuring the Forwarding-Delay Time, page 15-20 (optional)

• Configuring the Maximum-Aging Time, page 15-21 (optional)

• Configuring the Maximum-Hop Count, page 15-21 (optional)

• Specifying the Link Type to Ensure Rapid Transitions, page 15-22 (optional)

• Restarting the Protocol Migration Process, page 15-22 (optional)

Questions and Answers:

Need help?

Do you have a question about the Cisco 2950 - Catalyst Switch and is the answer not in the manual?

Cisco 2950 - Catalyst Switch Specifications

General