华为设备配置CE双归属

1. 在MPLS骨干网上配置IGP协议，实现骨干网PE和P的互通
   [PE1-LoopBack1]ip add 1.1.1.1 32
   [PE1-GigabitEthernet0/0/0]ip add 20.1.1.1 24
   [PE1]isis 1
   [PE1-isis-1]network-entity 10.0000.0000.0001.00
   [PE1-LoopBack1]isis enable 1
   [PE1-GigabitEthernet0/0/0]isis enable 1
   [P1-LoopBack1]ip add 2.2.2.2 32
   [P1-GigabitEthernet0/0/0]ip add 20.1.1.2 24
   [P1-GigabitEthernet0/0/1]ip add 30.1.1.2 24
   [P1]isis 1
   [P1-isis-1]network-entity 10.0000.0000.0002.00
   [P1-LoopBack1]isis enable 1
   [P1-GigabitEthernet0/0/0]isis enable 1
   [P1-GigabitEthernet0/0/1]isis enable 1
   [PE3-LoopBack1]ip add 3.3.3.3 32
   [PE3-GigabitEthernet0/0/0]ip add 30.1.1.3 24
   [PE3]isis 1
   [PE3-isis-1]network-entity 10.0000.0000.0003.00
   [PE3-LoopBack1]isis enable 1
   [PE3-GigabitEthernet0/0/0]isis enable 1
   [PE2-LoopBack1]ip add 4.4.4.4 32
   [PE2-GigabitEthernet0/0/0]ip add 40.1.1.4 24
   [PE2]isis 1
   [PE2-isis-1]network-entity 10.0000.0000.0004.00
   [PE2-LoopBack1]isis enable 1
   [PE2-GigabitEthernet0/0/0]isis enable 1
   [P2-LoopBack1]ip add 5.5.5.5 32
   [P2-GigabitEthernet0/0/0]ip add 40.1.1.5 24
   [P2-GigabitEthernet0/0/1]ip add 50.1.1.5 24
   [P2]isis 1
   [P2-isis-1]network-entity 10.0000.0000.0005.00
   [P2-LoopBack1]isis enable 1
   [P2-GigabitEthernet0/0/0]isis enable 1
   [P2-GigabitEthernet0/0/1]isis enable 1
   [PE4-LoopBack1]ip add 6.6.6.6 32
   [PE4-GigabitEthernet0/0/0]ip add 50.1.1.6 24
   [PE4]isis 1
   [PE4-isis-1]network-entity 10.0000.0000.0006.00
   [PE4-LoopBack1]isis enable 1
   [PE4-GigabitEthernet0/0/0]isis enable 1

2. 在MPLS骨干网上配置MPLS基本能力和MPLS LDP，建立LDP LSP
   [PE1]mpls lsr-id 1.1.1.1
   [PE1]mpls
   [PE1]mpls ldp
   [PE1-GigabitEthernet0/0/0]mpls
   [PE1-GigabitEthernet0/0/0]mpls ldp
   [P1]mpls lsr-id 2.2.2.2
   [P1]mpls
   [P1]mpls ldp
   [P1-GigabitEthernet0/0/0]mpls
   [P1-GigabitEthernet0/0/0]mpls ldp
   [P1-GigabitEthernet0/0/1]mpls
   [P1-GigabitEthernet0/0/1]mpls ldp
   [PE3]mpls lsr-id 3.3.3.3
   [PE3]mpls
   [PE3]mpls ldp
   [PE3-GigabitEthernet0/0/0]mpls
   [PE3-GigabitEthernet0/0/0]mpls ldp
   [PE2]mpls lsr-id 4.4.4.4
   [PE2]mpls
   [PE2]mpls ldp
   [PE2-GigabitEthernet0/0/0]mpls
   [PE2-GigabitEthernet0/0/0]mpls ldp
   [P2]mpls lsr-id 5.5.5.5
   [P2]mpls
   [P2]mpls ldp
   [P2-GigabitEthernet0/0/0]mpls
   [P2-GigabitEthernet0/0/0]mpls ldp
   [P2-GigabitEthernet0/0/1]mpls
   [P2-GigabitEthernet0/0/1]mpls ldp
   [PE4]mpls lsr-id 6.6.6.6
   [PE4]mpls
   [PE4]mpls ldp
   [PE4-GigabitEthernet0/0/0]mpls
   [PE4-GigabitEthernet0/0/0]mpls ldp
   
   

3. 在PE设备上配置VPN实例，将CE接入PE
   [PE1]ip vpn-instance vpn1
   [PE1-vpn-instance-vpn1]ipv4-family
   [PE1-vpn-instance-vpn1-af-ipv4]route-distinguisher 100:1
   [PE1-vpn-instance-vpn1-af-ipv4]vpn-target 1:1
   [PE1-GigabitEthernet0/0/1]ip binding vpn-instance vpn1
   [PE1-GigabitEthernet0/0/1]ip add 10.1.1.1 24
   [PE3]ip vpn-instance vpn1
   [PE3-vpn-instance-vpn1]ipv4-family
   [PE3-vpn-instance-vpn1-af-ipv4]route-distinguisher 100:3
   [PE3-vpn-instance-vpn1-af-ipv4]vpn-target 1:1
   [PE3-GigabitEthernet0/0/1]ip binding vpn-instance vpn1
   [PE3-GigabitEthernet0/0/1]ip add 10.3.1.3 24
   [PE2]ip vpn-instance vpn1
   [PE2-vpn-instance-vpn1]ipv4-family
   [PE2-vpn-instance-vpn1-af-ipv4]route-distinguisher 100:2
   [PE2-vpn-instance-vpn1-af-ipv4]vpn-target 1:1
   [PE2-GigabitEthernet0/0/1]ip binding vpn-instance vpn1
   [PE2-GigabitEthernet0/0/1]ip add 10.2.1.4 24
   [PE4]ip vpn-instance vpn1
   [PE4-vpn-instance-vpn1]ipv4-family
   [PE4-vpn-instance-vpn1-af-ipv4]route-distinguisher 100:4
   [PE4-vpn-instance-vpn1-af-ipv4]vpn-target 1:1
   [PE4-GigabitEthernet0/0/1]ip binding vpn-instance vpn1
   [PE4-GigabitEthernet0/0/1]ip add 10.4.1.6 24

4. 在PE之间建立MP-IBGP对等体关系
   [PE1]bgp 100
   [PE1-bgp]peer 3.3.3.3 as-number 100
   [PE1-bgp]peer 3.3.3.3 connect-interface LoopBack 1
   [PE1-bgp]ipv4-family vpnv4
   [PE1-bgp-af-vpnv4]peer 3.3.3.3 enable
   [PE3]bgp 100
   [PE3-bgp]peer 1.1.1.1 as-number 100
   [PE3-bgp]peer 1.1.1.1 connect-interface LoopBack 1
   [PE3-bgp]ipv4-family vpnv4
   [PE3-bgp-af-vpnv4]peer 1.1.1.1 enable
   [PE2]bgp 100
   [PE2-bgp]peer 6.6.6.6 as-number 100
   [PE2-bgp]peer 6.6.6.6 connect-interface LoopBack 1
   [PE2-bgp]ipv4-family vpnv4
   [PE2-bgp-af-vpnv4]peer 6.6.6.6 enable
   [PE4]bgp 100
   [PE4-bgp]peer 4.4.4.4 as-number 100
   [PE4-bgp]peer 4.4.4.4 connect-interface LoopBack 1
   [PE4-bgp]ipv4-family vpnv4
   [PE4-bgp-af-vpnv4]peer 4.4.4.4 enable
   
   

5. 在PE与CE之间配置EBGP路由协议，引入VPN路由
   [CE1-GigabitEthernet0/0/0]ip add 10.1.1.7 24
   [CE1-GigabitEthernet0/0/1]ip add 10.2.1.7 24
   [CE1-GigabitEthernet0/0/2]ip ad 1.5.1.7 24
   [CE1]bgp 65410
   [CE1-bgp]peer 10.1.1.1 as-number 100
   [CE1-bgp]peer 10.2.1.4 as-number 100
   [CE1-bgp]import-route direct
   [CE2-GigabitEthernet0/0/0]ip add 10.3.1.8 24
   [CE2-GigabitEthernet0/0/1]ip add 10.4.1.8 24
   [CE2-GigabitEthernet0/0/2]ip add 1.6.1.8 24
   [CE2]bgp 65420
   [CE2-bgp]peer 10.3.1.3 as-number 100
   [CE2-bgp]peer 10.4.1.6 as-number 100
   [CE2-bgp]import-route direct
   [PE1]bgp 100
   [PE1-bgp]ipv4-family vpn-instance vpn1
   [PE1-bgp-vpn1]peer 10.1.1.7 as-number 65410
   [PE1-bgp-vpn1]import-route direct
   [PE2]bgp 100
   [PE2-bgp]ipv4-family vpn-instance vpn1
   [PE2-bgp-vpn1]peer 10.2.1.7 as-number 65410
   [PE2-bgp-vpn1]import-route direct
   PE3]bgp 100
   [PE3-bgp]ipv4-family vpn-instance vpn1
   [PE3-bgp-vpn1]peer 10.3.1.8 as-number 65420
   [PE3-bgp-vpn1]import-route direct
   [PE4]bgp 100
   [PE4-bgp]ipv4-family vpn-instance vpn1
   [PE4-bgp-vpn1]peer 10.4.1.8 as-number 65420
   [PE4-bgp-vpn1]import-route direct
   

6. 在CE1上配置允许CE1到CE2的流量允许负载分担
   [CE1]bgp 65410
   [CE1-bgp]ipv4-family unicast
   [CE1-bgp-af-ipv4]maximum load-balancing 2

7. 配置路由策略，增大PE3上发布给CE2的BGP路由的MED值，使CE2到CE1的流量流经PE4，PE3作为备份
   [PE3]route-policy p1 permit node 10
   [PE3-route-policy]apply cost 120
   [PE3]bgp 100
   [PE3-bgp]ipv4-family vpn-instance vpn1
   [PE3-bgp-vpn1]peer 10.3.1.8 route-policy p1 export
   

发现对于到1.5.1.0/30的路由，PE3发布的MED值为120，比PE4发布的MED值大（缺省情况下MED的值为0），所以选择PE4发布的
8. 检查配置

看到去往对端CE2所接用户的路由，且是负载分担的

去往对端CE1所接用户的路由，且下一跳为10.4.1.6（PE4上接入CE2的接口IP地址）