API Guide

Table Of Contents
Flush MAC Addresses after a Topology Change
The system has an optimized MAC address flush mechanism for RSTP, MSTP, and PVST+ that flushes addresses only when necessary,
which allows for faster convergence during topology changes.
However, you may activate the flushing mechanism defined by 802.1Q-2003 using the tc-flush-standard command, which flushes
MAC addresses after every topology change notification.
To view the enable status of this feature, use the show running-config spanning-tree mstp command from EXEC Privilege
mode.
MSTP Sample Configurations
The running-configurations support the topology shown in the following illustration.
The configurations are from Dell Networking OS systems.
Figure 96. MSTP with Three VLANs Mapped to Two Spanning Tree Instances
Router 1 Running-Configuration
This example uses the following steps:
1. Enable MSTP globally and set the region name and revision map MSTP instances to the VLANs.
2. Assign Layer-2 interfaces to the MSTP topology.
3. Create VLANs mapped to MSTP instances tag interfaces to the VLANs.
(Step 1)
protocol spanning-tree mstp
no disable
name Tahiti
revision 123
MSTI 1 VLAN 100
MSTI 2 VLAN 200,300
!
(Step 2)
interface TenGigabitEthernet 1/21
no ip address
switchport
no shutdown
!
interface TenGigabitEthernet 1/31
no ip address
switchport
Multiple Spanning Tree Protocol (MSTP)
567