需求：
- 完成基本IP配置
- BGP234内运行OSPF（进程号100），激活MPLS
- 在PE上创建VRF，将PE-CE间的接口放入VRF；在PE和CE间运行IGP协议
- PE配置MP-BGP，建立MP-iBGP邻接关系
- 完成PE-CE之间的路由重发布
拓扑：
点击图片查看大图
配置:
CE1：
interface Loopback0 ip address 1.1.1.1 255.255.255.255 ! interface Ethernet0/0 ip address 192.168.1.254 255.255.255.0 ! interface Ethernet0/1 ip address 202.0.12.1 255.255.255.0 mpls ip #此处启用mpls只为能跟踪到mpls上的流量 ! interface Ethernet0/2 no ip address shutdown ! interface Ethernet0/3 no ip address shutdown ! router ospf 1 router-id 1.1.1.1 network 1.1.1.1 0.0.0.0 area 0 network 192.168.1.254 0.0.0.0 area 0 network 202.0.12.1 0.0.0.0 area 0 !
CE2：
interface Loopback0 ip address 5.5.5.5 255.255.255.255 ! interface Ethernet0/0 ip address 202.0.45.5 255.255.255.0 ! interface Ethernet0/1 ip address 192.168.2.254 255.255.255.0 ! interface Ethernet0/2 no ip address shutdown ! interface Ethernet0/3 no ip address shutdown ! router ospf 1 router-id 5.5.5.5 network 5.5.5.5 0.0.0.0 area 0 network 192.168.2.254 0.0.0.0 area 0 network 202.0.45.5 0.0.0.0 area 0 !
CE3：
interface Loopback0 ip address 6.6.6.6 255.255.255.0 ! interface Ethernet0/0 ip address 202.0.26.6 255.255.255.0 ! interface Ethernet0/1 ip address 192.168.1.254 255.255.255.0 ! interface Ethernet0/2 no ip address shutdown ! interface Ethernet0/3 no ip address shutdown ! router ospf 1 router-id 6.6.6.6 network 192.168.1.254 0.0.0.0 area 0 network 202.0.26.6 0.0.0.0 area 0 !
CE4：
interface Ethernet0/0 ip address 202.0.47.7 255.255.255.0 ! interface Ethernet0/1 ip address 192.168.2.254 255.255.255.0 ! interface Ethernet0/2 no ip address shutdown ! interface Ethernet0/3 no ip address shutdown ! router ospf 1 network 192.168.2.254 0.0.0.0 area 0 network 202.0.47.7 0.0.0.0 area 0 !
PE1：
ip vrf kenan #定义名为kenan的VRF rd 234:2 #设置RD值（AS号加编号） route-target export 234:2 #设置出方向的RT值（和对端PE的import对应） route-target import 234:4 #设置入方向的RT值（和对端PE的export对应） ! ip vrf xiaokun rd 234:5 route-target export 234:6 route-target import 234:7 ! ! ! ! mpls label range 200 299 #设置mpls标签范围（仅为方便实验观察，现网中请慎用） mpls ldp router-id Loopback0 # ! ! interface Loopback0 ip address 2.2.2.2 255.255.255.255 ! interface Ethernet0/0 ip vrf forwarding kenan #将接口划分给vrf（划分之后接口IP地址会被移除） ip address 202.0.12.2 255.255.255.0 ! interface Ethernet0/1 ip address 202.0.23.2 255.255.255.0 mpls ip #启用mpls ! interface Ethernet0/2 ip vrf forwarding xiaokun ip address 202.0.26.2 255.255.255.0 ! interface Ethernet0/3 no ip address shutdown ! router ospf 1 vrf kenan #配置PE和CE之间的动态路由（需在完成vrf配置之后，不然无法启动进程） redistribute bgp 234 subnets #将bgp重发布进此路由进程 network 202.0.12.2 0.0.0.0 area 0 ! router ospf 2 vrf xiaokun redistribute bgp 234 subnets network 202.0.26.2 0.0.0.0 area 0 ! router ospf 100 router-id 2.2.2.2 network 2.2.2.2 0.0.0.0 area 0 network 202.0.23.2 0.0.0.0 area 0 ! router bgp 234 bgp router-id 2.2.2.2 no bgp default ipv4-unicast #关闭bgp的ipv4单播 neighbor 4.4.4.4 remote-as 234 neighbor 4.4.4.4 update-source Loopback0 ! address-family vpnv4 #进入vpnv4地址族 neighbor 4.4.4.4 activate #激活邻居 neighbor 4.4.4.4 send-community extended exit-address-family ! address-family ipv4 vrf kenan redistribute ospf 1 match internal external 1 external 2 #将vrf的OSPF路由重发布进BGP（将所有OSPF的路由都重发布进来） exit-address-family ! address-family ipv4 vrf xiaokun redistribute ospf 2 match internal external 1 external 2 exit-address-family !
PE2：
ip vrf kenan rd 234:4 route-target export 234:4 route-target import 234:2 ! ip vrf xiaokun rd 234:5 route-target export 234:7 route-target import 234:6 ! ! ! mpls label range 400 499 mpls ldp router-id Loopback0 ! interface Loopback0 ip address 4.4.4.4 255.255.255.255 ! interface Ethernet0/0 ip address 202.0.34.4 255.255.255.0 mpls ip ! interface Ethernet0/1 ip vrf forwarding kenan ip address 202.0.45.4 255.255.255.0 ! interface Ethernet0/2 ip vrf forwarding xiaokun ip address 202.0.47.4 255.255.255.0 ! interface Ethernet0/3 no ip address shutdown ! router ospf 1 vrf kenan redistribute bgp 234 subnets network 202.0.45.4 0.0.0.0 area 0 ! router ospf 2 vrf xiaokun redistribute bgp 234 subnets network 202.0.47.4 0.0.0.0 area 0 ! router ospf 100 router-id 4.4.4.4 network 4.4.4.4 0.0.0.0 area 0 network 202.0.34.4 0.0.0.0 area 0 ! router bgp 234 bgp router-id 4.4.4.4 bgp log-neighbor-changes no bgp default ipv4-unicast neighbor 2.2.2.2 remote-as 234 neighbor 2.2.2.2 update-source Loopback0 ! address-family ipv4 neighbor 2.2.2.2 activate exit-address-family ! address-family vpnv4 neighbor 2.2.2.2 activate neighbor 2.2.2.2 send-community extended exit-address-family ! address-family ipv4 vrf kenan redistribute ospf 1 match internal external 1 external 2 exit-address-family ! address-family ipv4 vrf xiaokun redistribute ospf 2 match internal external 1 external 2 exit-address-family !
P：
mpls label range 300 399 mpls ldp router-id Loopback0 ! interface Loopback0 ip address 3.3.3.3 255.255.255.255 ! interface Ethernet0/0 ip address 202.0.23.3 255.255.255.0 mpls ip ! interface Ethernet0/1 ip address 202.0.34.3 255.255.255.0 mpls ip ! interface Ethernet0/2 no ip address shutdown ! interface Ethernet0/3 no ip address shutdown ! router ospf 100 router-id 3.3.3.3 network 3.3.3.3 0.0.0.0 area 0 network 202.0.23.3 0.0.0.0 area 0 network 202.0.34.3 0.0.0.0 area 0 !
PC1pingPC2，抓包发现确实是去了PC2（没有去PC4）：
点击图片查看大图
PC3pingPC4同理：
点击图片查看大图
