1.带下一跳的静态路由：
-----------------------R1----------------------------
R1(config)#ip route 2.2.2.0 255.255.255.0 12.1.1.2
R1(config)#ip route 23.1.1.0 255.255.255.0 12.1.1.2
R1(config)#ip route 3.3.3.0 255.255.255.0 12.1.1.2
----------------------R2-----------------------------
R2(config)#ip route 1.1.1.0 255.255.255.0 12.1.1.1
R2(config)#ip route 3.3.3.0 255.255.255.0 23.1.1.3
----------------------R3-----------------------------
R3(config)#ip route 1.1.1.0 255.255.255.0 23.1.1.2
R3(config)#ip route 12.1.1.0 255.255.255.0 23.1.1.2
R3(config)#ip route 2.2.2.0 255.255.255.0 23.1.1.2
验证实验结果：
R1#ping 3.3.3.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 3.3.3.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 56/60/64 ms
R2#ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 32/32/32 ms
R2#ping 3.3.3.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 3.3.3.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 32/32/32 ms
R3#ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 60/61/68 ms
R3#ping 2.2.2.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2.2.2.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 32/32/32 m
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