R1：
[R1]isis 启动ISIS
[R1-isis-1]is-level level-1 等级配置为1
[R1-isis-1]network-entity 47.0001.0000.0000.0001.00 配置区域ID和系统ID
[R1-isis-1]int e0/0/0
[R1-Ethernet0/0/0]isis enable 1 把这个接口划到ISIS中去
R2：
[R2]isis
[R2-isis-1]is-level level-1
[R2-isis-1]network-entity 47.0001.0000.0000.0002.00
[R2-isis-1]int e0/0/0
[R2-Ethernet0/0/0]isis enable 1
R3：
[R3]isis
[R3-isis-1]is-level level-1
[R3-isis-1]network-entity 47.0001.0000.0000.0003.00
[R3-isis-1]int e0/0/0
[R3-Ethernet0/0/0]isis enable 1
R4：
[R4]isis
[R4-isis-1]is-level level-1-2
[R4-isis-1]network-entity 47.0001.0000.0000.0004.00
[R4-Ethernet0/0/0]int e0/0/0
[R4-Ethernet0/0/1]isis enable 1
R5：
[R5]isis
[R5-isis-1]is-level level-1-2
[R5-isis-1]network-entity 47.0001.0000.0000.0005.00
[R5-isis-1]int e0/0/0
[R5-Ethernet0/0/1]isis enable 1
R6：
[R6]isis
[R6-isis-1]is-level level-2
[R6-isis-1]network-entity 47.0002.0000.0000.0006.00
[R6-Ethernet0/0/0]isis enable 1
[R6-Ethernet0/0/0]int e0/0/1
[R6-Ethernet0/0/1]isis enble 1
