MSTP是IEEE 802.1s中提出的一种STP和VLAN结合使用的新协议，它既继承了RSTP端口快速迁移的优点，又解决了RSTP中不同vlan必须运行在同一棵生成树上的问题。多生成树提出了域的概念，在域的内部可以生成多个生成树实例，并将VLAN关联到相应的实例中，每个VLAN只能关联到一个实例中。这样在域内部每个生成树实例就形成一个逻辑上的树拓扑结构，在域与域之间由CIST实例将各个域连成一个大的生成树。各个VLAN内的数据在不同的生成树实例内进行转发，这样就提供了负载均衡功能。本次实验主要操作多实例的配置工具/原料morewin7-64eNSP方法/步骤1/7分步阅读

一、搭建本次实验的拓扑结构

四台交换机，连接成环形结构

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二、配置所有交换机的VLAN

vlan batch 3 to 8 vlan batch 3 to 8 vlan batch 3 to 8 vlan batch 3 to 8

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三、配置本次实验的链路接口信息

dis th#interface GigabitEthernet0/0/1port link-type trunkport trunk allow-pass vlan 2 to 4094#

int e0/0/13dis thinterface Ethernet0/0/13port link-type trunkport trunk allow-pass vlan 2 to 4094#

port link-type trunk port trunk allow-pass vlan all bpdu enable

port link-type trunk port trunk allow-pass vlan all bpdu enable

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四、配置基本区域和两个实例

配置交换机属于同一个区域RG1，实例1与VLAN3、4、5建立映射关系，实例2与VLAN6、7、8建立映射关系，激活域配置

SW3：

stp region-configurationregion-name RG1revision-level 1instance 1 vlan 3 to 5instance 2 vlan 6 to 8active region-configuration

dis th#stp region-configurationregion-name 1revision-level 1instance 1 vlan 3 to 5instance 2 vlan 6 to 8active region-configuration#

dis th#stp region-configurationregion-name RG1revision-level 1instance 1 vlan 3 to 5instance 2 vlan 6 to 8active region-configuration

dis th #stp region-configurationregion-name RG1revision-level 1instance 1 vlan 3 to 5instance 2 vlan 6 to 8active region-configuration#

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五、配置上述的条件后查看当前所有交换机的MSTP信息

dis stp briMSTID Port Role STP State Protection 0 Ethernet0/0/13 ALTE DISCARDING NONE 0 GigabitEthernet0/0/1 ROOT FORWARDING NONE 1 Ethernet0/0/13 ROOT FORWARDING NONE 1 GigabitEthernet0/0/1 DESI FORWARDING NONE 2 Ethernet0/0/13 ROOT FORWARDING NONE 2 GigabitEthernet0/0/1 DESI FORWARDING NONE

dis stp briMSTID Port Role STP State Protection 0 Ethernet0/0/13 ALTE DISCARDING NONE 0 GigabitEthernet0/0/1 DESI FORWARDING NONE 0 GigabitEthernet0/0/2 ROOT FORWARDING NONE 1 Ethernet0/0/13 ROOT FORWARDING NONE 1 GigabitEthernet0/0/1 ALTE DISCARDING NONE 2 Ethernet0/0/13 ROOT FORWARDING NONE 2 GigabitEthernet0/0/1 ALTE DISCARDING NONE

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六、配置实例的优先级

stp instance 2 priority 0 stp instance 2 priority 4096 stp instance 2 priority 8192

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七、配置完实例的优先级后再查看MSTP信息

dis stp briMSTID Port Role STP State Protection 0 GigabitEthernet0/0/2 DESI FORWARDING NONE 0 GigabitEthernet0/0/9 DESI FORWARDING NONE 0 GigabitEthernet0/0/10 DESI FORWARDING NONE 0 GigabitEthernet0/0/13 DESI FORWARDING NONE 1 GigabitEthernet0/0/10 DESI FORWARDING NONE 1 GigabitEthernet0/0/13 DESI FORWARDING NONE 2 GigabitEthernet0/0/10 DESI FORWARDING NONE 2 GigabitEthernet0/0/13 DESI FORWARDING NONE

注意事项

注意实例的配置信息，实例的名字

观察root端口的变化