组网需求
如图所示,用户将网络划分为AS65008和AS65009,在AS65009内,使用IGP协议来计算路由(该例使用OSPF做为IGP协议)。要求实现两个AS之间的互相通信。
配置思路
采用如下的思路配置BGP与IGP交互:
- 在AR2、AR3和AR4上配置OSPF协议,使AR2、AR3和AR4之间可以互访。
- 在AR1和AR2上配置EBGP连接,使AR1和AR2之间可以通过BGP相互传递路由。
- 在AR2上配置BGP与OSPF互相引入,实现两个AS之间的互相通信。
- 在AR2上配置BGP路由聚合,可以简化BGP路由表规模。
操作步骤
配置IP
AR1
<Huawei>sys [Huawei]sys AR1 [AR1]int g0/0/0 [AR1-GigabitEthernet0/0/0]ip add 12.12.12.1 24 [AR1-GigabitEthernet0/0/0]q [AR1]int lo1 [AR1-LoopBack1]ip add 1.1.1.1 24 [AR1-LoopBack1]q
AR2
<Huawei>sys [Huawei]sys AR2 [AR2]int g0/0/0 [AR2-GigabitEthernet0/0/0]ip add 12.12.12.2 24 [AR2-GigabitEthernet0/0/0]q [AR2]int g0/0/1 [AR2-GigabitEthernet0/0/1]ip add 10.10.23.2 24 [AR2-GigabitEthernet0/0/1]q
AR3
<Huawei>sys [Huawei]sys AR3 [AR3]int g0/0/0 [AR3-GigabitEthernet0/0/0]ip add 10.10.23.3 24 [AR3-GigabitEthernet0/0/0]q [AR3]int g0/0/1 [AR3-GigabitEthernet0/0/1]ip add 10.10.34.3 24 [AR3-GigabitEthernet0/0/1]q [AR3]
AR4
<Huawei>sys [Huawei]sys AR4 [AR4]int g0/0/0 [AR4-GigabitEthernet0/0/0]ip add 10.10.34.4 24 [AR4-GigabitEthernet0/0/0]q
配置OSPF
公众号同名
AR2
[AR2]ospf [AR2-ospf-1]area 0 [AR2-ospf-1-area-0.0.0.0]network 10.10.23.0 0.0.0.255 [AR2-ospf-1-area-0.0.0.0]q
AR3
[AR3]ospf [AR3-ospf-1]area 0 [AR3-ospf-1-area-0.0.0.0]network 10.10.23.0 0.0.0.255 [AR3-ospf-1-area-0.0.0.0]network 10.10.34.0 0.0.0.255 [AR3-ospf-1-area-0.0.0.0]q
AR4
[AR4]ospf [AR4-ospf-1]area 0 [AR4-ospf-1-area-0.0.0.0]network 10.10.34.0 0.0.0.255 [AR4-ospf-1-area-0.0.0.0]q
在AR4上查看OSPF路由表
[AR4-ospf-1]display ospf routing OSPF Process 1 with Router ID 10.10.34.4 Routing Tables Routing for Network Destination Cost Type NextHop AdvRouter Area 10.10.34.0/24 1 Transit 10.10.34.4 10.10.34.4 0.0.0.0 10.10.23.0/24 2 Transit 10.10.34.3 12.12.12.2 0.0.0.0 Total Nets: 2 Intra Area: 2 Inter Area: 0 ASE: 0 NSSA: 0
配置BGP
AR1
[AR1]bgp 65008 [AR1-bgp]router-id 1.1.1.1 [AR1-bgp] peer 12.12.12.2 as-number 65009 # 单播发布路由 [AR1-bgp] ipv4-family unicast [AR1-bgp-af-ipv4]network 1.1.1.0 255.255.255.0
AR2
[AR2]bgp 65008 [AR2-bgp]router-id 2.2.2.2 [AR2-bgp] peer 12.12.12.1 as-number 65009
在AR2上查看BGP路由表
[AR2-bgp]display bgp routing-table BGP Local router ID is 2.2.2.2 Status codes: * - valid, > - best, d - damped, h - history, i - internal, s - suppressed, S - Stale Origin : i - IGP, e - EGP, ? - incomplete Total Number of Routes: 1 Network NextHop MED LocPrf PrefVal Path/Ogn *> 1.1.1.0/24 12.12.12.1 0 0 65008i [AR2-bgp]
配置路由引入
BGP路由引入到OSPF
AR2
[AR2]ospf [AR2-ospf-1]import-route bgp [AR2-ospf-1]q
再次在AR4上查看OSPF路由表
<AR4>display ospf routing OSPF Process 1 with Router ID 10.10.34.4 Routing Tables Routing for Network Destination Cost Type NextHop AdvRouter Area 10.10.34.0/24 1 Transit 10.10.34.4 10.10.34.4 0.0.0.0 10.10.23.0/24 2 Transit 10.10.34.3 12.12.12.2 0.0.0.0 Routing for ASEs Destination Cost Type Tag NextHop AdvRouter 1.1.1.0/24 1 Type2 1 10.10.34.3 12.12.12.2 Total Nets: 3 Intra Area: 2 Inter Area: 0 ASE: 1 NSSA: 0 <AR4>
OSPF路由引入到BGP
AR2
[AR2]bgp 65009 [AR2-bgp]ipv4-family unicast [AR2-bgp-af-ipv4]import-route ospf 1 [AR2-bgp-af-ipv4]q
再次在AR1上查看BGP路由表
<AR1>display bgp routing-table BGP Local router ID is 12.12.12.1 Status codes: * - valid, > - best, d - damped, h - history, i - internal, s - suppressed, S - Stale Origin : i - IGP, e - EGP, ? - incomplete Total Number of Routes: 3 Network NextHop MED LocPrf PrefVal Path/Ogn *> 1.1.1.0/24 0.0.0.0 0 0 i *> 10.10.23.0/24 12.12.12.2 0 0 65009? *> 10.10.34.0/24 12.12.12.2 2 0 65009?
验证AS之间互通
AR4 ping AR1的LoopBack1
<AR4>ping 1.1.1.1 PING 1.1.1.1: 56 data bytes, press CTRL_C to break Reply from 1.1.1.1: bytes=56 Sequence=1 ttl=253 time=60 ms Reply from 1.1.1.1: bytes=56 Sequence=2 ttl=253 time=30 ms Reply from 1.1.1.1: bytes=56 Sequence=3 ttl=253 time=40 ms Reply from 1.1.1.1: bytes=56 Sequence=4 ttl=253 time=40 ms Reply from 1.1.1.1: bytes=56 Sequence=5 ttl=253 time=40 ms --- 1.1.1.1 ping statistics --- 5 packet(s) transmitted 5 packet(s) received 0.00% packet loss round-trip min/avg/max = 30/42/60 ms #能ping即AS之间已互通
配置自动路由聚合
AR2
[AR2]bgp 65009 [AR2-bgp]ipv4-family unicast [AR2-bgp-af-ipv4]summary automatic
AR1上查看路由表
<AR1>display bgp routing-table BGP Local router ID is 12.12.12.1 Status codes: * - valid, > - best, d - damped, h - history, i - internal, s - suppressed, S - Stale Origin : i - IGP, e - EGP, ? - incomplete Total Number of Routes: 2 Network NextHop MED LocPrf PrefVal Path/Ogn *> 1.1.1.0/24 0.0.0.0 0 0 i *> 10.0.0.0 12.12.12.2 0 65009? <AR1>
聚合后再次验证互通
在AR1使用LoopBack1 ping AR4
<AR1>ping -a 1.1.1.1 10.10.34.4 PING 10.10.34.4: 56 data bytes, press CTRL_C to break Reply from 10.10.34.4: bytes=56 Sequence=1 ttl=253 time=30 ms Reply from 10.10.34.4: bytes=56 Sequence=2 ttl=253 time=50 ms Reply from 10.10.34.4: bytes=56 Sequence=3 ttl=253 time=40 ms Reply from 10.10.34.4: bytes=56 Sequence=4 ttl=253 time=10 ms Reply from 10.10.34.4: bytes=56 Sequence=5 ttl=253 time=40 ms --- 10.10.34.4 ping statistics --- 5 packet(s) transmitted 5 packet(s) received 0.00% packet loss round-trip min/avg/max = 10/34/50 ms <AR1>