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The configuration is as follows:
[R1] int s0/2/0
[R1-Serial0/2/0] ip add 10.1.12.1 30
[R1-Serial0/2/0] int lo0
[R1-LoopBack0] ip add 1.1.1.1 32
A [R1-LoopBack0] int lo1
[R1-LoopBack1] ip add 192.168.1.100 32
A [R1-LoopBack1] int lo2
[R1-LoopBack2] ip add 192.168.2.100 32
[R1-LoopBack2] int lo3
[R1-LoopBack3] ip add 192.168.3.100 32
[R1] rip
[R1-rip-1] ver 2
[R1-rip-1] undo sum
[R1-rip-1] net 10.1.12.0
[R1-rip-1] net 192.168.1.100
[R1-rip-1] net 192.168.2.100
[R1-rip-1] net 192.168.3.100
[R1-rip-1] net 1.1.1.1
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[R2] int s0/2/0
[R2-Serial0/2/0] ip add 10.1.12.2 30
[R2-Serial0/2/0] int s0/2/1
[R2-Serial0/2/1] ip add 10.1.23.1 30
[R2-Serial0/2/1] int lo0
[R2-LoopBack0] ip add 2.2.2.2 32
[R2] rip
[R2-rip-1] ver 2
[R2-rip-1] undo sum
[R2-rip-1] net 2.2.2.2
[R2-rip-1] net 10.1.12.0
[R2] ospf 1
[R2-ospf-1] area 0
[R2-ospf-1-area-0.0.0.0] net 10.1.23.0 0.0.0.3
[R2-ospf-1-area-0.0.0.0] net 2.2.2.2 0.0.0.0
[R2] rip
[R2-rip-1] import-route ospf
[R2] ospf
[R2-ospf-1] import-route rip
[R2-ospf-1] import-route direct
[R2] ip-prefix 1234 deny 192.168.3.100 32
[R2] ip-prefix 1234 permit 0.0.0.0 0 less-equal 32
[R2] rip
[R2-rip-1] filter-policy ip-prefix 1234 import
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[R3] int s0/2/0
[R3-Serial0/2/0] ip add 10.1.23.2 30
[R3-Serial0/2/0] int s0/2/1
[R3-Serial0/2/1] ip add 10.1.34.1 30
[R3-Serial0/2/1] int lo0
[R3-LoopBack0] ip add 3.3.3.3 32
[R3] ospf 1
[R3-ospf-1] area 0
[R3-ospf-1-area-0.0.0.0] net 10.1.23.0 0.0.0.3
[R3] isis 1
[R3-isis-1] network-entity 10.20..0000.0003.00
[R3-isis-1] int s0/2/1
[R3-Serial0/2/1] isis enable 1
[R3] int lo0
[R3-LoopBack0] isis enable 1
[R3] ospf
[R3-ospf-1] import-route isis
[R3] isis
[R3-isis-1] import-route ospf
[R3] ospf
[R3-ospf-1] import-route direct
[R3] ip-prefix 1234 deny 192.168.2.100 32
[R3] ip-prefix 1234 deny 192.168.3.100 32
[R3] ip-prefix 1234 permit 0.0.0.0 0 less-equal 32
[[R3] isis
[R3-isis-1] filter-policy ip-prefix 1234 export
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[R4] int s0/2/0
[R4-Serial0/2/0] ip add 10.1.24.2 30
[R4-Serial0/2/0] int lo0
[R4-LoopBack0] ip add 4.4.4.4 32
A [R4-LoopBack0] int lo1
[R4-LoopBack1] ip add 172.16.1.100 32
A [R4-LoopBack1] int lo2
[R4-LoopBack2] ip add 172.17.1.10032
[R4-LoopBack2] int lo3
[R4-LoopBack3] ip add 172.18.1.100 32
[R4] isis 1
[R4-isis-1] network-entity 10.20..0000.0004.00
[R4-isis-1] int s0/2/0
[R4-Serial0/2/0] isis enable 1
[R4-Serial0/2/0] int lo0
[R4-LoopBack0] isis enable
A [R4-LoopBack0] int lo1
[R4-LoopBack1] isi enable
A [R4-LoopBack1] int lo2
[R4-LoopBack2] isi enable
[R4-LoopBack2] int lo3
[R4-LoopBack3] isis enable
From maguanghua00 BLOG