Topology:
实验目的：理解Sham-link的使用场景。
说明：默认情况下，R5,R4互通，流量是经过直连链路。通过配置sham-link，R5，R4互通流量经过ISP，R4，R5之间的直连链路为备份链路。（假设R4，R5之间的链路为低带宽）
Step 1、配置各台路由器的IP地址，并且使用Ping命令确认各路由器的直连口的互通性。
| R1: lo 0:1.1.1.1/32 lo 1:11.11.11.11/32 s0/0:12.1.1.1/24 s0/1:15.1.1.1/24 R2: lo 0:2.2.2.2/32 s0/0:12.1.1.2/24 s0/1:23.1.1.2/24 R3: lo 0:3.3.3.3/32 lo 1:33.33.33.33/32 s0/0:23.1.1.3/24 s0/1:34.1.1.3/24 R4: lo 0:4.4.4.4/32 s0/0:34.1.1.4/24 f1/0:45.1.1.4/24 R5: lo 0:5.5.5.5/32 s0/1:15.1.1.5/24 f1/0:45.1.1.5/24 |
Step 2、在R1,R2,R3之间运行isis。
| R1: router isis net 49.0001.1111.1111.1111.00 int lo 0 ip router isis int s0/0 ip router isis |
| R2: router isis net 49.0001.2222.2222.2222.00 int lo 0 ip router isis int s0/0 ip router isis int s0/1 ip router isis |
| R3: router isis net 49.0001.3333.3333.3333.00 int lo 0 ip router isis int s0/0 ip router isis |
Step 3、启用ip cef。
| 全局模式下：ip cef |
Step 4、R1,R2,R3配置MPLS。
| R1: ip cef mpls label range 1000 1999 mpls label protocol ldp tag-switching tdp router-id Loopback0 int s0/0 mpls ip |
| R2: ip cef mpls label range 2000 2999 mpls label protocol ldp mpls ldp router-id lo 0 int s0/0 mpls ip int s0/1 mpls ip |
| R3: ip cef mpls label range 3000 3999 mpls label protocol ldp mpls ldp router-id lo 0 int s0/0 mpls ip |
Step 5、R1,R3配置VRF。
| R1: ip vrf AAA rd 100:1 route-target both 100:1 interface Loopback1 ip vrf forwarding AAA ip address 11.11.11.11 255.255.255.255 no clns route-cache ! interface Serial0/1 ip vrf forwarding AAA ip address 15.1.1.1 255.255.255.0 serial restart-delay 0 no clns route-cache ! |
| R3: ! ip vrf AAA rd 100:1 route-target export 100:1 route-target import 100:1 interface Loopback1 ip vrf forwarding AAA ip address 33.33.33.33 255.255.255.255 no clns route-cache interface Serial0/1 ip vrf forwarding AAA ip address 34.1.1.3 255.255.255.0 serial restart-delay 0 no clns route-cache ! |
Step 6、R1,R3配置MP-BGP。
| R1: router bgp 123 bgp router-id 1.1.1.1 no bgp default ipv4-unicast bgp log-neighbor-changes neighbor 3.3.3.3 remote-as 123 neighbor 3.3.3.3 update-source Loopback0 ! address-family vpnv4 neighbor 3.3.3.3 activate neighbor 3.3.3.3 send-community extended exit-address-family ! address-family ipv4 vrf AAA redistribute connected redistribute ospf 100 net 11.11.11.11 mask 255.255.255.255 no auto-summary no synchronization exit-address-family |
| R3: router bgp 123 bgp router-id 3.3.3.3 no bgp default ipv4-unicast bgp log-neighbor-changes neighbor 1.1.1.1 remote-as 123 neighbor 1.1.1.1 update-source Loopback0 ! address-family ipv4 neighbor 1.1.1.1 activate no auto-summary no synchronization exit-address-family ! address-family vpnv4 neighbor 1.1.1.1 activate neighbor 1.1.1.1 send-community extended exit-address-family ! address-family ipv4 vrf AAA redistribute connected redistribute ospf 100 net 33.33.33.33 mask 255.255.255.255 no auto-summary no synchronization exit-address-family |
Step 7、R4,R5配置ospf 100。
| R1: router ospf 100 vrf AAA log-adjacency-changes area 0 sham-link 11.11.11.11 33.33.33.33 redistribute bgp 123 subnets network 15.1.1.0 0.0.0.255 area 0 |
| R3: router ospf 100 vrf AAA log-adjacency-changes area 0 sham-link 33.33.33.33 11.11.11.11 redistribute bgp 123 subnets network 34.1.1.0 0.0.0.255 area 0 |
Step 8、查看的相关命令以及测试结果。
| R1#show ip ospf 100 sh Sham Link OSPF_SL0 to address 33.33.33.33 is up Area 0 source address 11.11.11.11 Run as demand circuit DoNotAge LSA allowed. Cost of using 1 State POINT_TO_POINT, Timer intervals configured, Hello 10, Dead 40, Wait 40, Hello due in 00:00:05 Adjacency State FULL (Hello suppressed) Index 2/2, retransmission queue length 0, number of retransmission 1 First 0x0(0)/0x0(0) Next 0x0(0)/0x0(0) Last retransmission scan length is 1, maximum is 1 Last retransmission scan time is 0 msec, maximum is 0 msec |