MSTP（多生成树协议）

MSTP：多生成树协议（华为交换机默认允许MSTP）

工作原理：将多个VLAN捆绑在一起，运行在一个STP实例里面，不同实例间的STP互相独立

注：默认情况下所有VLAN都在实例0里面

SW1——创建VLAN

system-view     //进入全局配置模式
[Huawei]undo info-center enable     //关闭告警提示
[Huawei]sysname SW1     //改名
[SW1]vlan batch 10 20     //创建VLAN10和VLAN20

SW2——创建VLAN

system-view     //进入全局配置模式 
[Huawei]undo info-center enable     //关闭告警提示 
[Huawei]sysname SW2     //改名
[SW2]vlan batch 10 20     //创建VLAN10和VLAN20

SW3——创建VLAN

system-view     //进入全局配置模式 
[Huawei]undo info-center enable     //关闭告警提示 
[Huawei]sysname SW3     //改名
[SW3]vlan batch 10 20     //创建VLAN10和VLAN20

SW1——连接PC设置链路为access

[SW1]interface g0/0/3     //进入接口
[SW1-GigabitEthernet0/0/3]port link-type access     //将接口设为access链路
[SW1-GigabitEthernet0/0/3]port default vlan 10     //允许VLAN10通过
[SW1-GigabitEthernet0/0/3]quit     //退出
[SW1]

SW2——连接PC设置链路为access

[SW2]interface g0/0/3     //进入接口
[SW2-GigabitEthernet0/0/3]port link-type access     //将接口设为access链路 
[SW2-GigabitEthernet0/0/3]port default vlan 20     //允许VLAN20通过
[SW2-GigabitEthernet0/0/3]quit     //退出
[SW2]

SW3——连接PC设置链路为access

[SW3]interface g0/0/3     //进入接口
[SW3-GigabitEthernet0/0/3]port link-type access     //将接口设为access链路 
[SW3-GigabitEthernet0/0/3]port default vlan 10     //允许VLAN10通过	
[SW3-GigabitEthernet0/0/3]quit     //退出 
[SW3]interface g0/0/4     //进入接口
[SW3-GigabitEthernet0/0/4]port link-type access     //将接口设为access链路 
[SW3-GigabitEthernet0/0/4]port default vlan 20     //允许VLAN20通过
[SW3-GigabitEthernet0/0/4]quit     //退出
[SW3]

SW1——连接交换机设置链路为trunk

[SW1]port-group group-member g0/0/1 to g0/0/2     //将两个端口加入端口组
[SW1-port-group]port link-type trunk     //将端口组里面的端口设置为trunk链路
[SW1-GigabitEthernet0/0/1]port link-type trunk 
[SW1-GigabitEthernet0/0/2]port link-type trunk 	
[SW1-port-group]port trunk allow-pass vlan all     //允许所有VLAN通过 
[SW1-GigabitEthernet0/0/1]port trunk allow-pass vlan all 
[SW1-GigabitEthernet0/0/2]port trunk allow-pass vlan all 
[SW1-port-group]quit     //退出
[SW1]

SW2——连接交换机设置链路为trunk

[SW2]port-group group-member g0/0/1 to g0/0/2     //将两个端口加入端口组
[SW2-port-group]port link-type trunk     //将端口组里面的端口设置为trunk链路 
[SW2-GigabitEthernet0/0/1]port link-type trunk 
[SW2-GigabitEthernet0/0/2]port link-type trunk 	
[SW2-port-group]port trunk allow-pass vlan all     //允许所有VLAN通过  
[SW2-GigabitEthernet0/0/1]port trunk allow-pass vlan all 
[SW2-GigabitEthernet0/0/2]port trunk allow-pass vlan all 
[SW2-port-group]quit     //退出
[SW2]

SW3——连接交换机设置链路为trunk

[SW3]port-group group-member g0/0/1 to g0/0/2     //将两个端口加入端口组
[SW3-port-group]port link-type trunk     //将端口组里面的端口设置为trunk链路 
[SW3-GigabitEthernet0/0/1]port link-type trunk 
[SW3-GigabitEthernet0/0/2]port link-type trunk 	
[SW3-port-group]port trunk allow-pass vlan all     //允许所有VLAN通过  
[SW3-GigabitEthernet0/0/1]port trunk allow-pass vlan all 
[SW3-GigabitEthernet0/0/2]port trunk allow-pass vlan all 
[SW3-port-group]quit     //退出
[SW3]

SW2——查看交换机那个端阻塞

[SW2]dis stp brief     //查看STP信息
 MSTID  Port                        Role  STP State     Protection
   0    GigabitEthernet0/0/1        ALTE  DISCARDING      NONE     //端口为阻塞端口
   0    GigabitEthernet0/0/2        ROOT  FORWARDING      NONE
   0    GigabitEthernet0/0/3        DESI  FORWARDING      NONE

SW1——SMTP配置

[SW1]stp region-configuration     //激活SMTP域配置
[SW1-mst-region]region-name huawei     //设置SMTP域名字
[SW1-mst-region]instance 1 vlan 10     //将VLAN10划分到实例1里面	
[SW1-mst-region]instance 2 vlan 20     //将VLAN20划分到实例2里面
[SW1-mst-region]active region-configuration     //激活MST域的配置
[SW1-mst-region]quit     //退出
[SW1]

SW2——SMTP配置

[SW2]stp region-configuration     //激活SMTP域配置
[SW2-mst-region] region-name huawei     //设置SMTP域名字
[SW2-mst-region] instance 1 vlan 10     //将VLAN10划分到实例1里面
[SW2-mst-region] instance 2 vlan 20     //将VLAN20划分到实例2里面
[SW2-mst-region] active region-configuration     //激活MST域的配置
[SW2-mst-region]quit     //退出 
[SW2]

SW3——SMTP配置

[SW3]stp region-configuration     //激活SMTP域配置
[SW3-mst-region] region-name huawei     //设置SMTP域名字
[SW3-mst-region] instance 1 vlan 10     //将VLAN10划分到实例1里面
[SW3-mst-region] instance 2 vlan 20     //将VLAN20划分到实例2里面
[SW3-mst-region] active region-configuration     //激活MST域的配置
[SW3-mst-region]quit     //退出
[SW3]

SW2—查看实例1中阻塞端口

[SW2]dis stp instance 1 brief     //查看实例1中端口状态
 MSTID  Port                        Role  STP State     Protection
   1    GigabitEthernet0/0/1        ROOT  FORWARDING      NONE
   1    GigabitEthernet0/0/2        DESI  DISCARDING      NONE     //阻塞端口
[SW2]

针对实例1数据包通信过程

SW2——实例2中，将次交换机的优先级调为最低，成为根桥

[SW2]stp instance 2 priority 4096     //实例2中将交换机的优先级调为最低，成为根桥

SW2——查看实例2中的交换机优先级

[SW2]dis stp instance 2     //查看实例2中交换机优先级
-------[MSTI 2 Global Info]-------
MSTI Bridge ID      :4096.4c1f-ccc5-27fc     //实例2中，此交换机的优先级最低
MSTI RegRoot/IRPC   :4096.4c1f-ccc5-27fc / 0
MSTI RootPortId     :0.0
Master Bridge       :32768.4c1f-cc25-682f
Cost to Master      :20000
TC received         :9
TC count per hello  :0
Time since last TC  :0 days 0h:2m:35s
Number of TC        :8
Last TC occurred    :GigabitEthernet0/0/1
 ----[Port1(GigabitEthernet0/0/1)][FORWARDING]----
 Port Role           :Designated Port
 Port Priority       :128
 Port Cost(Dot1T )   :Config=auto / Active=20000
 Designated Bridge/Port   :4096.4c1f-ccc5-27fc / 128.1
 Port Times          :RemHops 20
 TC or TCN send      :4
 TC or TCN received  :5
 ----[Port2(GigabitEthernet0/0/2)][FORWARDING]----
 Port Role           :Designated Port
 Port Priority       :128
 Port Cost(Dot1T )   :Config=auto / Active=20000
 Designated Bridge/Port   :4096.4c1f-ccc5-27fc / 128.2
 Port Times          :RemHops 20
 TC or TCN send      :5
 TC or TCN received  :4
 ----[Port3(GigabitEthernet0/0/3)][FORWARDING]----
 Port Role           :Designated Port
 Port Priority       :128
 Port Cost(Dot1T )   :Config=auto / Active=20000
 Designated Bridge/Port   :4096.4c1f-ccc5-27fc / 128.3
 Port Times          :RemHops 20
 TC or TCN send      :7
 TC or TCN received  :0
[SW2]

SW2—实例2中，将SW2配置为根桥，将SW1配置为备份根桥

[SW2]stp instance 2 root primary     //SW2交换机会自动降低优先级成为实例2的根桥
[SW1]stp instance 2 root secondary     //SW1交换机会自动成为备份根桥

SW1——查看实例2中，阻塞的端口

[SW1]dis stp instance 2 brief     //查看实例2中，端口状态
 MSTID  Port                        Role  STP State     Protection
   2    GigabitEthernet0/0/1        ROOT  FORWARDING      NONE
   2    GigabitEthernet0/0/2        DESI  DISCARDING      NONE     //实例2中，该端口被阻塞
[SW1]

针对实例2数据包通信过程