经典bgp路由黑洞的解决之道
1、做基本配置
enabl
conf t
hostname r5
no ip domain-lookup
ip subnet-zero
line con 0
pass
word 123
logg sy
exec-t 0 0
exit
line vty 0 4
pass
word 123
login
exit
2、做接口。。。
en
config t
int s1/0
ip add 35.1.1.1 255.255.255.0
no shutdown
exit
int s2/0
ip add 35.1.1.2 255.255.255.0
no shutdown
exit
int loopback 0
ip add 3.3.3.3 255.255.255.0
no shutdown
exit
3 做通
show ip int bri
ping连接自己的端口
4、在AS65245 中， 启动OSPF协议， 目的，实现BGP底层的可达。。
------------------------------------------------------------------------------
r4
router os 10
router-id 4.4.4.4
network 24.1.1.0 0.0.0.255 area 0
network 45.1.1.0 0.0.0.255 area 0
network 4.4.4.4 0.0.0.0 area 0
r2
router os 10
router-id 2.2.2.2
network 24.1.1.0 0.0.0.255 area 0
network 12.1.1.0 0.0.0.255 area 0
network 2.2.2.2 0.0.0.0 area 0
passive-
interface s2/0
r5
router ospf 10
router-id 5.5.5.5
network 45.1.1.2 0.0.0.0 area 0
network 35.1.1.1 0.0.0.0 area 0
network 5.5.5.5 0.0.0.0 area 0
passive-interface s1/0
-----------------------------------------------------------------------------------
R4(config)#router os 10
R4(config-router)#router-id 4.4.4.4
R4(config-router)#network 24.1.1.0 0.0.0.255 area 0
R4(config-router)#network 45.1.1.0 0.0.0.255 area 0
R4(config-router)#network 4.4.4.4 0.0.0.0 area 0
R2(config)#router os 10
R2(config-router)#router-id 2.2.2.2
R2(config-router)#network 24.1.1.0 0.0.0.255 area 0
R2(config-router)#network 12.1.1.0 0.0.0.255 area 0
R2(config-router)#network 2.2.2.2 0.0.0.0 area 0
R2(config-router)#passive-interface s2/0
R5(config)#router ospf 10
R5(config-router)#router-id 5.5.5.5
R5(config-router)#network 45.1.1.2 0.0.0.0 area 0
R5(config-router)#network 35.1.1.1 0.0.0.0 area 0
R5(config-router)#network 5.5.5.5 0.0.0.0 area 0
R5(config-router)#passive-interface s1/0
5、验证OSPF的启动。。
r2loopback ping r5loopback
r2ping 5.5.5.5
r5#ping 2.2.2.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 24.1.1.1, timeout is 2 seconds:
!!!!!
r2#ping 45.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 45.1.1.2, timeout is 2 seconds:
!!!!
6、启动BGP
------------------------------------------------------------------------------------
r1
----------------------------------------------------------------------------------------
R1(config)#router bgp 65001
R1(config-router)#bgp router-id 1.1.1.1
R1(config-router)#neighbor 12.1.1.2 remote-as 65245
R1(config-router)#network 1.1.1.0 mask 255.255.255.0
R2(config)#router bgp 65245
R2(config-router)#bgp router-id 2.2.2.2
R2(config-router)#neighbor 12.1.1.1 remote-as 65001
R2(config-router)#exit
R2#show ip bgp summary 查看邻居
R2#show ip bgp summary
BGP router identifier 2.2.2.2, local AS number 65245
BGP table version is 2, main routing table version 2
1 network entries using 101 bytes of memory
1 path entries using 48 bytes of memory
1 BGP path attribute entries using 60 bytes of memory
1 BGP AS-PATH entries using 24 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 233 total bytes of memory
BGP activity 1/0 prefixes, 1/0 paths, scan interval 60 secs
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
12.1.1.1 4 65001 5 4 2 0 0 00:00:40 1
R2#
R2(config-router)#neighbor 5.5.5.5 remote-as 65245
R2(config-router)#neighbor 5.5.5.5 update-source loopback 0
R5(config)#router bgp 65245
R5(config-router)#bgp router-id 5.5.5.5
R5(config-router)#neighbor 2.2.2.2 remote-as 65245
R5(config-router)#neighbor 2.2.2.2 update-source loopback 0
show ip bgp summary
R5(config)#router bgp 65245
R5(config-router)#neighbor 35.1.1.2 remote-as 65003
R3(config)#router bgp 65003
R3(config-router)#bgp router-id 3.3.3.3
R3(config-router)#neighbor 35.1.1.1 remote-as 65245
R3(config-router)#network 3.3.3.0 mask 255.255.255.0
show ip bgp summary
R3#show ip bgp ------查看BGP表
BGP table version is 3, local router ID is 3.3.3.3
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 1.1.1.0/24 35.1.1.5 0 65245 65001 i
*> 3.3.3.0/24 0.0.0.0 0 32768 i
解决方案：
1、全互联的IBGP
2、RR（路由器反射器)
3、联邦
4、MPLS
5、连线
6、Trunnel
7、静态路由
8、重发布
