MSTP是IEEE802.1s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
win7-64
eNSP
方法/步骤
1、搭建本次实验的拓扑结构四台交换机，连接成环形结构
2、配置所有交换机的VLAN[S1]vlanbatch3to8[S2]vlanbatch3to8[S3]vlanbatch3to8[S4]vlanbatch3to8
3、配置本次实验的链锭缠愁颊路接口信息[SW1-GigabitEthernet0/0/1]disth#interfaceGigabitEthernet0/0/1portlink-typetru荏鱿胫协nkporttrunkallow-passvlan2to4094#[SW1-GigabitEthernet0/0/1]inte0/0/13[SW1-Ethernet0/0/13]disthinterfaceEthernet0/0/13portlink-typetrunkporttrunkallow-passvlan2to4094#[SW3-GigabitEthernet0/0/10]portlink-typetrunk[SW3-GigabitEthernet0/0/10]porttrunkallow-passvlanall[SW3-GigabitEthernet0/0/10]bpduenable[SW4-GigabitEthernet0/0/10]portlink-typetrunk[SW4-GigabitEthernet0/0/10]porttrunkallow-passvlanall[SW4-GigabitEthernet0/0/10]bpduenable
4、配置基本区域和两个实麻质跹礼例配置交换机属于同一个区域RG1，实例1与VLAN5建立映射关系，实例2与VLAN7斤舻浑趸、8建立映射关系，激活域配置SW3：stpregion-configurationregion-nameRG1revision-level1instance1vlan3to5instance2vlan6to8activeregion-configuration[SW4-mst-region]disth#stpregion-configurationregion-name1revision-level1instance1vlan3to5instance2vlan6to8activeregion-configuration#[SW1-mst-region]disth#stpregion-configurationregion-nameRG1revision-level1instance1vlan3to5instance2vlan6to8activeregion-configuration[SW2-mst-region]disth#stpregion-configurationregion-nameRG1revision-level1instance1vlan3to5instance2vlan6to8activeregion-configuration#
5、配置上啄醴荇侧述的条件后查看当前所有交换机的MSTP信息[SW2]disstpbriMSTIDPortRoleSTPStateProtection0呶蓟鹭毵Ethernet0/0/13ALTEDISCARDINGNONE0GigabitEthernet0/0/1ROOTFORWARDINGNONE1Ethernet0/0/13ROOTFORWARDINGNONE1GigabitEthernet0/0/1DESIFORWARDINGNONE2Ethernet0/0/13ROOTFORWARDINGNONE2GigabitEthernet0/0/1DESIFORWARDINGNONE[SW1]disstpbriMSTIDPortRoleSTPStateProtection0Ethernet0/0/13ALTEDISCARDINGNONE0GigabitEthernet0/0/1DESIFORWARDINGNONE0GigabitEthernet0/0/2ROOTFORWARDINGNONE1Ethernet0/0/13ROOTFORWARDINGNONE1GigabitEthernet0/0/1ALTEDISCARDINGNONE2Ethernet0/0/13ROOTFORWARDINGNONE2GigabitEthernet0/0/1ALTEDISCARDINGNONE
6、配置实例的优先级[SW4]stpinstance2priority0[SW3]stpinstance2priority4096[SW2]stpinstance2priority8192
7、配置完实例的优先级后再查看MSTP信息[SW4]disstpbriMSTIDPortRoleSTPStateProtection0GigabitEthernet0/0/2DESIFORWARDINGNONE0GigabitEthernet0/0/9DESIFORWARDINGNONE0GigabitEthernet0/0/10DESIFORWARDINGNONE0GigabitEthernet0/0/13DESIFORWARDINGNONE1GigabitEthernet0/0/10DESIFORWARDINGNONE1GigabitEthernet0/0/13DESIFORWARDINGNONE2GigabitEthernet0/0/10DESIFORWARDINGNONE2GigabitEthernet0/0/13DESIFORWARDINGNONE
