1. 配置各接口所属的VLAN
   [LSW1]vlan 10
   [LSW1-GigabitEthernet0/0/1]port link-type trunk
   [LSW1-GigabitEthernet0/0/1]port trunk allow-pass vlan 10
   [LSW2]vlan 10
   [LSW2-GigabitEthernet0/0/1]port link-type trunk
   [LSW2-GigabitEthernet0/0/1]port trunk allow-pass vlan 10
   [LSW3]vlan 10
   [LSW3-GigabitEthernet0/0/1]port link-type trunk
   [LSW3-GigabitEthernet0/0/1]port trunk allow-pass vlan 10
   [LSW4]vlan 10
   [LSW4-GigabitEthernet0/0/1]port link-type trunk
   [LSW4-GigabitEthernet0/0/1]port trunk allow-pass vlan 10
   [LSW5]vlan 10
   [LSW5-GigabitEthernet0/0/1]port link-type trunk
   [LSW5-GigabitEthernet0/0/1]port trunk allow-pass vlan 10
   [LSW5-GigabitEthernet0/0/2]port link-type trunk
   [LSW5-GigabitEthernet0/0/2]port trunk allow-pass vlan 10
   [LSW5-GigabitEthernet0/0/3]port link-type trunk
   [LSW5-GigabitEthernet0/0/3]port trunk allow-pass vlan 10
   [LSW5-GigabitEthernet0/0/4]port link-type trunk
   [LSW5-GigabitEthernet0/0/4]port trunk allow-pass vlan 10

2. 配置各VLANIF接口的IP地址
   [LSW1-Vlanif10]ip add 10.1.1.1 24
   [LSW2-Vlanif10]ip add 10.1.1.2 24
   [LSW3-Vlanif10]ip add 10.1.1.3 24
   [LSW4-Vlanif10]ip add 10.1.1.4 24

3. 查看各台LSW上VLANIF10的MAC地址
   
   
   
   

4. 配置IS-IS基本功能
   [LSW1]isis 1
   [LSW1-isis-1]network-entity 10.0000.0000.0001.00
   [LSW1-Vlanif10]isis enable 1
   [LSW2]isis 1
   [LSW2-isis-1]network-entity 10.0000.0000.0002.00
   [LSW2-Vlanif10]isis enable 1
   [LSW3]isis 1
   [LSW3-isis-1]is-level level-1
   [LSW3-isis-1]network-entity 10.0000.0000.0003.00
   [LSW3-Vlanif10]isis enable 1
   [LSW4]isis 1
   [LSW4-isis-1]is-level level-2
   [LSW4-isis-1]network-entity 10.0000.0000.0004.00
   [LSW4-Vlanif10]isis enable 1
   
   
   
   

从接口信息中可以看到，在使用缺省DIS优先级的情况下，在Level-1 和Level-2级别的设备中，LSW1接口的MAC地址最大，因此为DIS
5. 配置LSW2的DIS优先级
[LSW2-Vlanif10]isis dis-priority 100 // 默认是64，越大越优

6. 验证配置
   

可以看到，在改变IS-IS接口的DIS优先级后，LSW2即成为Level-1和Level-2的DIS