配置四台pc的IP（不同网段）、子网掩码、网关 10.0.1.2 255.255.255.0 10.0.1.1 10.0.2.2 255.255.255.0 10.0.2.1 10.0.3.2 255.255.255.0 10.0.3.1 10.0.4.2 255.255.255.0 10.0.4.1

中间层两台交换机命令如下（例：左）

vlan 10

vlan 20

region-name yh instance 1 vlan 10 instance 2 vlan 20 instance 3 vlan 30 instance 4 vlan 40 active region-configuration

stp global enable

interface GigabitEthernet1/0/1 port link-mode bridge port access vlan 10

interface GigabitEthernet1/0/2 port link-mode bridge port access vlan 20

interface GigabitEthernet1/0/3 port link-mode bridge port link-type trunk port trunk permit vlan 1 10 20

interface GigabitEthernet1/0/4 port link-mode bridge port link-type trunk port trunk permit vlan 1 10 20

上层两台交换机配置命令如下（例：左）

vlan 10

vlan 20

vlan 30

vlan 40

stp region-configuration region-name yh instance 1 vlan 10 instance 2 vlan 20 instance 3 vlan 30 instance 4 vlan 40 active region-configuration

stp instance 1 3 root primary stp instance 2 4 root secondary stp global enable

interface Bridge-Aggregation1 port link-type trunk port trunk permit vlan 1 10 20 30 40 link-aggregation mode dynamic

interface GigabitEthernet1/0/1 port link-mode bridge port link-type trunk port trunk permit vlan 1 10 20

interface GigabitEthernet1/0/2 port link-mode bridge port link-type trunk port trunk permit vlan 1 30 40

interface GigabitEthernet1/0/20 port link-mode bridge port link-type trunk port trunk permit vlan 1 10 20 30 40 port link-aggregation group 1

interface GigabitEthernet1/0/21 port link-mode bridge port link-type trunk port trunk permit vlan 1 10 20 30 40 port link-aggregation group 1

实验结果图：

理清vlan与交换机之间的关系 中间层交换机建立相连pc的VLAN 上层交换机建立所有存在的VLAN（允许通过所有VLAN） 理清生成树实例 中间层和上层的交换机都要创建所有的VLAN对应的实例 注意上层交换机间的链路聚合 创建聚合组，放行所有VLAN