第9章 MPLS和MPLS VPN-9.1 MPLS基础

4.利用MPLS解决BGP路由黑洞

R1配置，OSPF不宣告192.168.1.0/24网段

[R1]interface GigabitEthernet 0/0/0
[R1-GigabitEthernet0/0/0]IP address 12.1.1.1 8
[R1]interface GigabitEthernet 0/0/1
[R1-GigabitEthernet0/0/1]ip address 192.168.1.254 24
[R1]interface LoopBack 0
[R1-LoopBack0]ip address 1.1.1.1 32

[R1]ospf 1 router-id 1.1.1.1
[R1-ospf-1]area 0
[R1-ospf-1-area-0.0.0.0]network 12.1.1.0 0.255.255.255
[R1-ospf-1-area-0.0.0.0]network 1.1.1.1 0.0.0.0

[R1]mpls ls
[R1]mpls lsr-id 1.1.1.1
[R1-mpls]quit
[R1]mpls ldp
[R1]interface GigabitEthernet 0/0/0
[R1-GigabitEthernet0/0/0]mpls 
[R1-GigabitEthernet0/0/0]mpls ldp  
[R1]interface GigabitEthernet 0/0/1
[R1-GigabitEthernet0/0/1]mpls
[R1-GigabitEthernet0/0/1]mpls ldp

[R1]bgp 1234
[R1-bgp]router-id 1.1.1.1
[R1-bgp]peer 4.4.4.4 as-number 1234
[R1-bgp]peer 4.4.4.4 connect-interface LoopBack 0
[R1-bgp]network 192.168.1.0 24

2）R2配置

[R2]interface GigabitEthernet 0/0/0
[R2-GigabitEthernet0/0/0]ip address 12.1.1.2 8
[R2]interface GigabitEthernet 0/0/1
[R2-GigabitEthernet0/0/1]ip address 23.1.1.2 8
[R2]interface LoopBack 0
[R2-LoopBack0]ip address 2.2.2.2 32

[R2]ospf 1 router-id 2.2.2.2 
[R2-ospf-1]area 0
[R2-ospf-1-area-0.0.0.0]network 12.1.1.0 0.255.255.255
[R2-ospf-1-area-0.0.0.0]network 23.1.1.0 0.255.255.255
[R2-ospf-1-area-0.0.0.0]network 2.2.2.2 0.0.0.0

[R2]mpls lsr-id 2.2.2.2
[R2]mpls 
[R2-mpls]quit
[R2]mpls ldp 
[R2-mpls-ldp]quit

[R2]interface GigabitEthernet 0/0/0
[R2-GigabitEthernet0/0/0]mpls 
[R2-GigabitEthernet0/0/0]mpls ldp 
[R2-GigabitEthernet0/0/0]quit
[R2]interface GigabitEthernet 0/0/1
[R2-GigabitEthernet0/0/1]mpls                            
[R2-GigabitEthernet0/0/1]mpls ldp

3）R3配置

[R3]interface GigabitEthernet 0/0/0
[R3-GigabitEthernet0/0/0]ip address 23.1.1.3 8
[R3]interface GigabitEthernet 0/0/1
[R3-GigabitEthernet0/0/1]ip address 34.1.1.3 8
[R3]interface LoopBack 0
[R3-LoopBack0]ip address 3.3.3.3 32

[R3]ospf 1 router-id 3.3.3.3
[R3-ospf-1]area 0
[R3-ospf-1-area-0.0.0.0]network 23.1.1.0 0.255.255.255 
[R3-ospf-1-area-0.0.0.0]network 34.1.1.0 0.255.255.255
[R3-ospf-1-area-0.0.0.0]network 3.3.3.3 0.0.0.0 

[R3]mpls lsr-id 3.3.3.3
[R3-mpls]quit
[R3]mpls ldp 

[R3]interface GigabitEthernet 0/0/0
[R3-GigabitEthernet0/0/0]mpls
[R3-GigabitEthernet0/0/0]mpls ldp
[R3-GigabitEthernet0/0/0]quit
[R3]interface GigabitEthernet 0/0/1
[R3-GigabitEthernet0/0/1]mpls
[R3-GigabitEthernet0/0/1]mpls ldp

4）R4配置，OSPF不宣告192.168.4.0/24网段

[R4]interface GigabitEthernet 0/0/0
[R4-GigabitEthernet0/0/0]ip address 34.1.1.4 8
[R4]interface GigabitEthernet 0/0/1
[R4-GigabitEthernet0/0/1]ip address 192.168.4.254 24
[R4]interface LoopBack 0
[R4-LoopBack0]ip address 4.4.4.4 32

[R4]ospf 1 router-id 4.4.4.4
[R4-ospf-1]area 0
[R4-ospf-1-area-0.0.0.0]network 34.1.1.0 0.255.255.255
[R4-ospf-1-area-0.0.0.0]network 4.4.4.4 0.0.0.0

[R4]mpls lsr-id 4.4.4.4
[R4]mpls
[R4-mpls]quit
[R4]mpls ldp 
[R4-mpls-ldp]quit

[R4]interface GigabitEthernet 0/0/0
[R4-GigabitEthernet0/0/0]mpls
[R4-GigabitEthernet0/0/0]mpls ldp
[R4]interface GigabitEthernet 0/0/1
[R4-GigabitEthernet0/0/1]mpls
[R4-GigabitEthernet0/0/1]mpls ldp

[R4]bgp 1234
[R4-bgp]router-id 4.4.4.4
[R4-bgp]peer 1.1.1.1 as-number 1234
[R4-bgp]peer 1.1.1.1 connect-interface LoopBack 0
[R4-bgp]network 192.168.4.0 24

5）查看路由信息

[R1]display ip  routing-table 
Destination/Mask    Proto   Pre  Cost      Flags NextHop         Interface

              2.2.2.2/32  OSPF    10   1           D   12.1.1.2        GigabitEthernet0/0/0
        3.3.3.3/32  OSPF    10   2           D   12.1.1.2        GigabitEthernet0/0/0
        4.4.4.4/32  OSPF    10   3           D   12.1.1.2        GigabitEthernet0/0/0    
       23.0.0.0/8   OSPF    10   2           D   12.1.1.2        GigabitEthernet0/0/0
       34.0.0.0/8   OSPF    10   3           D   12.1.1.2        GigabitEthernet0/0/0
       192.168.4.0/24  IBGP    255  0          RD   4.4.4.4         GigabitEthernet0/0/0

6）R1、R4配置激活递归隧道功能，报文通过MPLS转发，实现192.168.1.0和192.168.4.0网段互通。

[R1]ip ip-prefix 1 permit 192.168.4.0 24
[R1]route recursive-lookup tunnel ip-prefix 1

[R4]ip ip-prefix 1 permit 192.168.1.0 24
[R4]route recursive-lookup tunnel ip-prefix 1

[R1]display fib 192.168.4.0 24
  Route Entry Count: 1
Destination/Mask   Nexthop         Flag  TimeStamp     Interface      TunnelID
192.168.4.0/24     12.1.1.2        DGU   t[4563]       GE0/0/0        0x5

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