1. 使能LSW3和LSW4的生成树计算功能
   [LSW3]vlan 100
   [LSW3]stp enable
   [LSW3-GigabitEthernet0/0/1]port link-type hybrid
   [LSW3-GigabitEthernet0/0/1]port hybrid pvid vlan 100
   [LSW3-GigabitEthernet0/0/1]port hybrid untagged vlan 100
   [LSW4]vlan 100
   [LSW4]stp enable
   [LSW4-GigabitEthernet0/0/1]port link-type hybrid
   [LSW4-GigabitEthernet0/0/1]port hybrid pvid vlan 100
   [LSW4-GigabitEthernet0/0/1]port hybrid untagged vlan 100
   2.使能LSW1和LSW2二层协议透明传输功能
   [LSW1]vlan 100
   [LSW1-GigabitEthernet0/0/2]port link-type hybrid
   [LSW1-GigabitEthernet0/0/2]port hybrid pvid vlan 100
   [LSW1-GigabitEthernet0/0/2]port hybrid untagged vlan 100
   [LSW1-GigabitEthernet0/0/2]l2protocol-tunnel stp enable
   [LSW1-GigabitEthernet0/0/1]port link-type trunk
   [LSW1-GigabitEthernet0/0/1]port trunk allow-pass vlan 100
   [LSW2]vlan 100
   [LSW2-GigabitEthernet0/0/1]port link-type trunk
   [LSW2-GigabitEthernet0/0/1]port trunk allow-pass vlan 100
   [LSW2-GigabitEthernet0/0/2]port link-type hybrid
   [LSW2-GigabitEthernet0/0/2]port hybrid pvid vlan 100
   [LSW2-GigabitEthernet0/0/2]port hybrid untagged vlan 100
   [LSW2-GigabitEthernet0/0/2]l2protocol-tunnel stp enable
2. 配置LSW1和LSW2替换接收到LSW3和LSW4的STP协议报文的目的MAC地址
   [LSW1]l2protocol-tunnel stp group-mac 0100-0100-0100
   [LSW2]l2protocol-tunnel stp group-mac 0100-0100-0100
3. 配置LSW4的优先级为4096
   [LSW4]stp priority 4096
4. 检查配置