Configuring Mstp Features - Cisco Catalyst 2950 Software Configuration Manual

Chapter 14 Configuring MSTP
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Configuring MSTP Features

These sections describe how to configure basic MSTP features:
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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 IEEE 802.1D switches, RSTP selectively
sends IEEE 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 IEEE 802.1D BPDU after the port migration-delay timer has expired, it
assumes that it is connected to an IEEE 802.1D switch and starts using only IEEE 802.1D BPDUs.
However, if the RSTP switch is using IEEE 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.
Default MSTP Configuration, page 14-12
MSTP Configuration Guidelines, page 14-12
Specifying the MST Region Configuration and Enabling MSTP, page 14-13
Configuring the Root Switch, page 14-14
Configuring a Secondary Root Switch, page 14-16
Configuring the Port Priority, page 14-17
Configuring the Path Cost, page 14-18
Configuring the Switch Priority, page 14-19
Configuring the Hello Time, page 14-19
Configuring the Forwarding-Delay Time, page 14-20
Configuring the Maximum-Aging Time, page 14-21
Configuring the Maximum-Hop Count, page 14-21
Specifying the Link Type to Ensure Rapid Transitions, page 14-22
Restarting the Protocol Migration Process, page 14-22
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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
Configuring MSTP Features
(required)
(optional)
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