华为OSPF、BGP路由反射器配置详解

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爱草坪 2018-10-14 12:19:15 ©著作权

文章标签 OSPF BGP 文章分类 网络安全

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对于网络工程师而言，OSPF、BGP的重要性不言而喻，本篇文章我们就来回顾下OSPF、BGP的配置技巧，重点如下 1.熟悉DHCP配置； 2.熟悉OSFP配置； 3.BGP路由反射器配置
入下图所示，要求如下： 1.网络拓扑规划如图所示； 2.PC1、PC2、PC3全部自动获取ip地址； 3.R1、R2、R3之间运行osfp保证网络的联通性； 4.PC1、PC2、PC3之间网络互通

第一步配置OSPF保证路由器直接网络连通性 R1配置如下： [R1]dhcp enable Info: The operation may take a few seconds. Please wait for a moment.done. [R1]interface g0/0/2 [R1-GigabitEthernet0/0/2]ip address 192.168.1.254 24 [R1-GigabitEthernet0/0/2]dhcp select interface [R1]interface g0/0/0 [R1-GigabitEthernet0/0/0]ip address 192.168.12.1 24 [R1-GigabitEthernet0/0/0]q [R1]interface LoopBack 0 [R1-LoopBack0]ip address 10.10.1.1 24 [R1-LoopBack0]q [R1-ospf-1]area 0 [R1-ospf-1-area-0.0.0.0]network 192.168.12.0 0.0.0.255 [R1-ospf-1-area-0.0.0.0]network 10.10.1.1 255.255.255.255 R2配置如下： [R2]dhcp enable Info: The operation may take a few seconds. Please wait for a moment.done. [R2]interface g0/0/2 [R2-GigabitEthernet0/0/2]ip address 192.168.2.254 24 [R2-GigabitEthernet0/0/2]dhcp select interface [R2]interface g0/0/1 [R2-GigabitEthernet0/0/1]ip address 192.168.12.2 24. [R2-GigabitEthernet0/0/1]q [R2]interface g0/0/0 [R2-GigabitEthernet0/0/0]ip address 192.168.23.2 24. [R2-GigabitEthernet0/0/0]q [R2]interface LoopBack 0 [R2-LoopBack0]ip address 10.10.2.2 24 [R2-LoopBack0]q [R2-ospf-1]area 0 [R2-ospf-1-area-0.0.0.0]network 192.168.12.0 0.0.0.255 [R2-ospf-1-area-0.0.0.0]network 192.168.23.0 0.0.0.255 [R2-ospf-1-area-0.0.0.0]network 10.10.2.2 255.255.255.255 R3配置如下： [R2]dhcp enable Info: The operation may take a few seconds. Please wait for a moment.done. [R3]interface g0/0/2 [R3-GigabitEthernet0/0/2]ip address 192.168.3.254 24 [R3-GigabitEthernet0/0/2]dhcp select interface [R3]interface g0/0/1 [R3-GigabitEthernet0/0/1]ip address 192.168.23.3 24 [R3]interface LoopBack 0 [R3-LoopBack0]ip address 10.10.3.3 24 [R3-LoopBack0]q [R3-ospf-1]area 0 [R3-ospf-1-area-0.0.0.0]network 192.168.23.0 0.0.0.255 [R3-ospf-1-area-0.0.0.0]network 10.10.3.3 255.255.255.255 测试路由器直接连通性：在R1上ping路由器R3，网络互通 [R1]ping 10.10.3.3 PING 10.10.3.3: 56 data bytes, press CTRL_C to break Reply from 10.10.3.3: bytes=56 Sequence=1 ttl=254 time=40 ms Reply from 10.10.3.3: bytes=56 Sequence=2 ttl=254 time=20 ms Reply from 10.10.3.3: bytes=56 Sequence=3 ttl=254 time=30 ms Reply from 10.10.3.3: bytes=56 Sequence=4 ttl=254 time=30 ms Reply from 10.10.3.3: bytes=56 Sequence=5 ttl=254 time=50 ms

--- 10.10.3.3 ping statistics --- 5 packet(s) transmitted 5 packet(s) received 0.00% packet loss round-trip min/avg/max = 20/34/50 ms
第二步配置bgp R1配置如下 [R1]bgp [R1]bgp 64512 [R1-bgp]peer 10.10.2.2 as-number 64512 [R1-bgp]peer 10.10.2.2 connect-interface LoopBack 0 [R1-bgp]import-route direct [R1-bgp]router-id 1.1.1.1 R2配置如下 [R2]bgp 64512 [R2-bgp]router-id 2.2.2.2 [R2-bgp]peer 10.10.1.1 as-number 64512 [R2-bgp]peer 10.10.1.1 connect-interface LoopBack 0 [R2-bgp]peer 10.10.3.3 as-number 64512 [R2-bgp]peer 10.10.3.3 connect-interface LoopBack 0 [R2-bgp]import-route direct R3配置如下 [R3]bgp [R3]bgp 64512 [R3-bgp]peer 10.10.2.2 as-number 64512 [R3-bgp]peer 10.10.2.2 connect-interface LoopBack 0 [R3-bgp]import-route direct [R3-bgp]router-id 3.3.3.3
此时查看R1bgp路由表和R3的路由表如下; bgp路由表 [R1]display bgp routing-table

BGP Local router ID is 1.1.1.1 Status codes: * - valid, > - best, d - damped, h - history, i - internal, s - suppressed, S - Stale Origin : i - IGP, e - EGP, ? - incomplete

Total Number of Routes: 12 Network NextHop MED LocPrf PrefVal Path/Ogn

*> 10.10.1.0/24 0.0.0.0 0 0 ? *> 10.10.1.1/32 0.0.0.0 0 0 ? *>i 10.10.2.0/24 10.10.2.2 0 100 0 ? *> 127.0.0.0 0.0.0.0 0 0 ? *> 127.0.0.1/32 0.0.0.0 0 0 ? *> 192.168.1.0 0.0.0.0 0 0 ? *> 192.168.1.254/32 0.0.0.0 0 0 ? *>i 192.168.2.0 10.10.2.2 0 100 0 ? *> 192.168.12.0 0.0.0.0 0 0 ?

i 10.10.2.2 0 100 0 ? *> 192.168.12.1/32 0.0.0.0 0 0 ? *>i 192.168.23.0 10.10.2.2 0 100 0 ? [R3]dis ip routing-table Route Flags: R - relay, D - download to fib Routing Tables: Public Destinations : 18 Routes : 18

Destination/Mask Proto Pre Cost Flags NextHop Interface

  10.10.1.1/32  OSPF    10   2           D   192.168.23.2    GigabitEthernet

0/0/1 10.10.2.0/24 IBGP 255 0 RD 10.10.2.2 GigabitEthernet 0/0/1 10.10.2.2/32 OSPF 10 1 D 192.168.23.2 GigabitEthernet 0/0/1 10.10.3.0/24 Direct 0 0 D 10.10.3.3 LoopBack0 10.10.3.3/32 Direct 0 0 D 127.0.0.1 LoopBack0 10.10.3.255/32 Direct 0 0 D 127.0.0.1 LoopBack0 127.0.0.0/8 Direct 0 0 D 127.0.0.1 InLoopBack0 127.0.0.1/32 Direct 0 0 D 127.0.0.1 InLoopBack0 127.255.255.255/32 Direct 0 0 D 127.0.0.1 InLoopBack0 192.168.2.0/24 IBGP 255 0 RD 10.10.2.2 GigabitEthernet 0/0/1 192.168.3.0/24 Direct 0 0 D 192.168.3.254 GigabitEthernet 0/0/2 192.168.3.254/32 Direct 0 0 D 127.0.0.1 GigabitEthernet 0/0/2 192.168.3.255/32 Direct 0 0 D 127.0.0.1 GigabitEthernet 0/0/2 192.168.12.0/24 OSPF 10 2 D 192.168.23.2 GigabitEthernet 0/0/1 192.168.23.0/24 Direct 0 0 D 192.168.23.3 GigabitEthernet 0/0/1 192.168.23.3/32 Direct 0 0 D 127.0.0.1 GigabitEthernet 0/0/1 192.168.23.255/32 Direct 0 0 D 127.0.0.1 GigabitEthernet 0/0/1 255.255.255.255/32 Direct 0 0 D 127.0.0.1 InLoopBack0

可以总结如下，可以看到，由于IBGP 遵守水平分割规则，R2不能将学习到的路由互相转发，造成R1与R3不能学习到对方的路由。PC1与PC2不能ping通。
在R2上配置路由反射器，使R1和R3成为了R2路由反射器配置如下 [R2]bgp 64512 [R2-bgp]peer 10.10.1.1 reflect-client [R2-bgp]peer 10.10.3.3 reflect-client

R1的路由表和bgp路由表如下： [R1]display bgp routing-table

BGP Local router ID is 1.1.1.1 Status codes: * - valid, > - best, d - damped, h - history, i - internal, s - suppressed, S - Stale Origin : i - IGP, e - EGP, ? - incomplete

Total Number of Routes: 14 Network NextHop MED LocPrf PrefVal Path/Ogn

*> 10.10.1.0/24 0.0.0.0 0 0 ? *> 10.10.1.1/32 0.0.0.0 0 0 ? *>i 10.10.2.0/24 10.10.2.2 0 100 0 ? *>i 10.10.3.0/24 10.10.3.3 0 100 0 ? *> 127.0.0.0 0.0.0.0 0 0 ? *> 127.0.0.1/32 0.0.0.0 0 0 ? *> 192.168.1.0 0.0.0.0 0 0 ? *> 192.168.1.254/32 0.0.0.0 0 0 ? *>i 192.168.2.0 10.10.2.2 0 100 0 ? *>i 192.168.3.0 10.10.3.3 0 100 0 ? *> 192.168.12.0 0.0.0.0 0 0 ?

i 10.10.2.2 0 100 0 ? *> 192.168.12.1/32 0.0.0.0 0 0 ? *>i 192.168.23.0 10.10.2.2 0 100 0 ? [R1]dis ip ro [R1]dis ip routing-table Route Flags: R - relay, D - download to fib Routing Tables: Public Destinations : 20 Routes : 20

Destination/Mask Proto Pre Cost Flags NextHop Interface

  10.10.1.0/24  Direct  0    0           D   10.10.1.1       LoopBack0
  10.10.1.1/32  Direct  0    0           D   127.0.0.1       LoopBack0
10.10.1.255/32  Direct  0    0           D   127.0.0.1       LoopBack0
  10.10.2.0/24  IBGP    255  0          RD   10.10.2.2       GigabitEthernet

0/0/0 10.10.2.2/32 OSPF 10 1 D 192.168.12.2 GigabitEthernet 0/0/0 10.10.3.0/24 IBGP 255 0 RD 10.10.3.3 GigabitEthernet 0/0/0 10.10.3.3/32 OSPF 10 2 D 192.168.12.2 GigabitEthernet 0/0/0 127.0.0.0/8 Direct 0 0 D 127.0.0.1 InLoopBack0 127.0.0.1/32 Direct 0 0 D 127.0.0.1 InLoopBack0 127.255.255.255/32 Direct 0 0 D 127.0.0.1 InLoopBack0 192.168.1.0/24 Direct 0 0 D 192.168.1.254 GigabitEthernet 0/0/2 192.168.1.254/32 Direct 0 0 D 127.0.0.1 GigabitEthernet 0/0/2 192.168.1.255/32 Direct 0 0 D 127.0.0.1 GigabitEthernet 0/0/2 192.168.2.0/24 IBGP 255 0 RD 10.10.2.2 GigabitEthernet 0/0/0 192.168.3.0/24 IBGP 255 0 RD 10.10.3.3 GigabitEthernet 0/0/0 192.168.12.0/24 Direct 0 0 D 192.168.12.1 GigabitEthernet 0/0/0 192.168.12.1/32 Direct 0 0 D 127.0.0.1 GigabitEthernet 0/0/0 192.168.12.255/32 Direct 0 0 D 127.0.0.1 GigabitEthernet 0/0/0 192.168.23.0/24 OSPF 10 2 D 192.168.12.2 GigabitEthernet 0/0/0 255.255.255.255/32 Direct 0 0 D 127.0.0.1 InLoopBack0

可以总结看到，路由反射器将从客户处学到的路由转发给除此客户外的所有的客户，R1与R3可以学习到对方的路由。PC1与PC3可以ping通。
测试PC1、PC2、PC3网络互通 PC>ping 192.168.3.253

Ping 192.168.3.253: 32 data bytes, Press Ctrl_C to break From 192.168.3.253: bytes=32 seq=1 ttl=125 time=31 ms From 192.168.3.253: bytes=32 seq=2 ttl=125 time=32 ms From 192.168.3.253: bytes=32 seq=3 ttl=125 time=31 ms From 192.168.3.253: bytes=32 seq=4 ttl=125 time=15 ms From 192.168.3.253: bytes=32 seq=5 ttl=125 time=32 ms