BGP详解3
八、配置样例1
下面的示例中涉及到BGP的基本配置，涉及到一些基本的知识点，如EBGP多跳、更新源使用环回接口、路由映射发布团体属性等，如下图所示。
![clip_image022[4]](http://img1.51cto.com/attachment/201012/27/499334_1293422562AUFM.jpg "clip_image022[4]")
下面是其参考配置。
R1#sh running-config
!
interface Loopback0
ip address 192.168.250.1 255.255.255.0
!
interface Loopback1
ip address 192.168.1.213 255.255.255.252
!
interface Loopback6
ip address 5.5.5.5 255.255.255.0
!
interface Serial2/0
ip address 192.168.1.210 255.255.255.252
serial restart-delay 0
!
router bgp 300
no synchronization
bgp log-neighbor-changes
network 192.168.1.212 mask 255.255.255.252
network 192.168.250.0
neighbor 6.6.6.6 remote-as 100
neighbor 6.6.6.6 ebgp-multihop 2
neighbor 6.6.6.6 update-source Loopback6
no auto-summary
!
ip route 6.6.6.0 255.255.255.0 192.168.1.209
!
R2#sh running-config
!
interface Loopback5
ip address 1.1.1.1 255.255.255.255
!
interface Loopback6
ip address 6.6.6.6 255.255.255.0
!
interface Ethernet1/0
ip address 192.168.1.221 255.255.255.252
duplex half
!
interface Ethernet1/1
ip address 192.168.1.193 255.255.255.252
duplex half
!
!
interface Serial2/0
ip address 192.168.1.209 255.255.255.252
serial restart-delay 0
!
interface Serial2/1
ip address 192.168.1.226 255.255.255.252
serial restart-delay 0
!
router ospf 10
log-adjacency-changes
passive-interface Serial2/0
passive-interface Serial2/1
network 1.1.1.1 0.0.0.0 area 0
network 192.168.1.192 0.0.0.3 area 0
network 192.168.1.220 0.0.0.3 area 0
!
router bgp 100
no synchronization
bgp log-neighbor-changes
neighbor 2.2.2.2 remote-as 100
neighbor 2.2.2.2 update-source Loopback5
neighbor 2.2.2.2 next-hop-self
neighbor 3.3.3.3 remote-as 100
neighbor 3.3.3.3 update-source Loopback5
neighbor 3.3.3.3 next-hop-self
neighbor 5.5.5.5 remote-as 300
neighbor 5.5.5.5 ebgp-multihop 2
neighbor 5.5.5.5 update-source Loopback6
neighbor 192.168.1.225 remote-as 200
no auto-summary
!
ip route 5.5.5.0 255.255.255.0 192.168.1.210
!
R3#sh running-config
!
interface Loopback5
ip address 2.2.2.2 255.255.255.255
!
interface Ethernet1/0
ip address 192.168.1.222 255.255.255.252
duplex half
!
interface Ethernet1/1
ip address 192.168.1.198 255.255.255.252
duplex half
!
router ospf 10
log-adjacency-changes
network 2.2.2.2 0.0.0.0 area 0
network 192.168.1.196 0.0.0.3 area 0
network 192.168.1.220 0.0.0.3 area 0
!
router bgp 100
no synchronization
bgp log-neighbor-changes
neighbor 1.1.1.1 remote-as 100
neighbor 1.1.1.1 update-source Loopback5
neighbor 3.3.3.3 remote-as 100
neighbor 3.3.3.3 update-source Loopback5
no auto-summary
!
R4#sh running-config
!
interface Loopback5
ip address 3.3.3.3 255.255.255.255
!
interface Ethernet1/0
ip address 192.168.1.194 255.255.255.252
duplex half
!
interface Ethernet1/1
ip address 192.168.1.197 255.255.255.252
duplex half
!
interface Ethernet1/2
ip address 192.168.1.206 255.255.255.252
duplex half
!
!
router ospf 10
log-adjacency-changes
passive-interface Ethernet1/2
network 3.3.3.3 0.0.0.0 area 0
network 192.168.1.192 0.0.0.3 area 0
!
router bgp 100
no synchronization
bgp log-neighbor-changes
neighbor 1.1.1.1 remote-as 100
neighbor 1.1.1.1 update-source Loopback5
neighbor 1.1.1.1 next-hop-self
neighbor 2.2.2.2 remote-as 100
neighbor 2.2.2.2 update-source Loopback5
neighbor 2.2.2.2 next-hop-self
neighbor 192.168.1.205 remote-as 400
no auto-summary
!
R5#sh running-config
!
interface Loopback0
ip address 192.168.50.1 255.255.255.0
!
interface Loopback1
ip address 192.168.75.1 255.255.255.0
!
interface Loopback3
ip address 192.168.1.201 255.255.255.252
!
interface Ethernet1/0
ip address 192.168.1.205 255.255.255.252
duplex half
!
router bgp 400
no synchronization
bgp log-neighbor-changes
network 192.168.1.200 mask 255.255.255.252
network 192.168.50.0
network 192.168.75.0
neighbor 192.168.1.206 remote-as 100
no auto-summary
!
R6#sh running-config
!
interface Loopback0
ip address 192.168.100.1 255.255.255.0
!
interface Loopback1
ip address 192.168.200.1 255.255.255.0
!
interface Loopback3
ip address 192.168.1.217 255.255.255.252
!
interface Loopback10
ip address 192.168.192.1 255.255.255.0
!
interface Loopback11
ip address 192.168.193.1 255.255.255.0
!
interface Loopback12
ip address 192.168.194.1 255.255.255.0
!
interface Loopback13
ip address 192.168.195.1 255.255.255.0
!
interface Loopback14
ip address 192.168.196.1 255.255.255.0
!
interface Loopback15
ip address 192.168.197.1 255.255.255.0
!
interface Loopback16
ip address 192.168.198.1 255.255.255.0
!
interface Loopback17
ip address 192.168.199.1 255.255.255.0
!
interface Serial2/0
ip address 192.168.1.225 255.255.255.252
serial restart-delay 0
!
router bgp 200
no synchronization
bgp log-neighbor-changes
network 192.168.1.216 mask 255.255.255.252
network 192.168.100.0
network 192.168.192.0
network 192.168.193.0
network 192.168.194.0
network 192.168.195.0
network 192.168.196.0
network 192.168.197.0
network 192.168.198.0
network 192.168.199.0
network 192.168.200.0
aggregate-address 192.168.192.0 255.255.248.0
neighbor 192.168.1.226 remote-as 100
neighbor 192.168.1.226 send-community
neighbor 192.168.1.226 route-map community out
no auto-summary
!
!
no ip http server
no ip http secure-server
!
!
access-list 110 permit ip host 192.168.192.0 host 255.255.248.0
!
route-map community permit 10
match ip address 110
set community none
!
route-map community permit 20
set community no-export
!
使用一些常用命令来查看其状态信息，如下所示：
R2#sh ip bgp
BGP table version is 18, local router ID is 6.6.6.6
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
*>i192.168.1.200/30 3.3.3.3 0 100 0 400 i
*> 192.168.1.212/30 5.5.5.5 0 0 300 i
*> 192.168.1.216/30 192.168.1.225 0 0 200 i
*>i192.168.50.0 3.3.3.3 0 100 0 400 i
*>i192.168.75.0 3.3.3.3 0 100 0 400 i
*> 192.168.100.0 192.168.1.225 0 0 200 i
*> 192.168.192.0 192.168.1.225 0 0 200 i
*> 192.168.192.0/21 192.168.1.225 0 0 200 i
*> 192.168.193.0 192.168.1.225 0 0 200 i
*> 192.168.194.0 192.168.1.225 0 0 200 i
*> 192.168.195.0 192.168.1.225 0 0 200 i
*> 192.168.196.0 192.168.1.225 0 0 200 i
*> 192.168.197.0 192.168.1.225 0 0 200 i
*> 192.168.198.0 192.168.1.225 0 0 200 i
*> 192.168.199.0 192.168.1.225 0 0 200 i
*> 192.168.200.0 192.168.1.225 0 0 200 i
*> 192.168.250.0 5.5.5.5 0 0 300 i
R2#sh ip bgp summary
BGP router identifier 6.6.6.6, local AS number 100
BGP table version is 18, main routing table version 18
17 network entries using 1989 bytes of memory
17 path entries using 884 bytes of memory
5/4 BGP path/bestpath attribute entries using 620 bytes of memory
3 BGP AS-PATH entries using 72 bytes of memory
1 BGP community 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 3589 total bytes of memory
BGP activity 17/0 prefixes, 17/0 paths, scan interval 60 secs
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
2.2.2.2 4 100 15 18 18 0 0 00:12:09 0
3.3.3.3 4 100 16 18 18 0 0 00:12:17 3
5.5.5.5 4 300 16 18 18 0 0 00:12:49 2
192.168.1.225 4 200 17 18 18 0 0 00:12:03 12
R4#sh ip bgp
BGP table version is 18, 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
*> 192.168.1.200/30 192.168.1.205 0 0 400 i
*>i192.168.1.212/30 1.1.1.1 0 100 0 300 i
*>i192.168.1.216/30 1.1.1.1 0 100 0 200 i
*> 192.168.50.0 192.168.1.205 0 0 400 i
*> 192.168.75.0 192.168.1.205 0 0 400 i
*>i192.168.100.0 1.1.1.1 0 100 0 200 i
*>i192.168.192.0 1.1.1.1 0 100 0 200 i
*>i192.168.192.0/21 1.1.1.1 0 100 0 200 i
*>i192.168.193.0 1.1.1.1 0 100 0 200 i
*>i192.168.194.0 1.1.1.1 0 100 0 200 i
*>i192.168.195.0 1.1.1.1 0 100 0 200 i
*>i192.168.196.0 1.1.1.1 0 100 0 200 i
*>i192.168.197.0 1.1.1.1 0 100 0 200 i
*>i192.168.198.0 1.1.1.1 0 100 0 200 i
*>i192.168.199.0 1.1.1.1 0 100 0 200 i
*>i192.168.200.0 1.1.1.1 0 100 0 200 i
*>i192.168.250.0 1.1.1.1 0 100 0 300 i
R4#sh ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
B 192.168.192.0/24 [200/0] via 1.1.1.1, 00:12:47
1.0.0.0/32 is subnetted, 1 subnets
O 1.1.1.1 [110/11] via 192.168.1.193, 00:13:28, Ethernet1/0
B 192.168.193.0/24 [200/0] via 1.1.1.1, 00:12:47
2.0.0.0/32 is subnetted, 1 subnets
O 2.2.2.2 [110/21] via 192.168.1.193, 00:13:28, Ethernet1/0
B 192.168.194.0/24 [200/0] via 1.1.1.1, 00:12:47
B 192.168.75.0/24 [20/0] via 192.168.1.205, 00:12:49
3.0.0.0/32 is subnetted, 1 subnets
C 3.3.3.3 is directly connected, Loopback5
B 192.168.195.0/24 [200/0] via 1.1.1.1, 00:12:47
B 192.168.196.0/24 [200/0] via 1.1.1.1, 00:12:47
B 192.168.197.0/24 [200/0] via 1.1.1.1, 00:12:47
B 192.168.198.0/24 [200/0] via 1.1.1.1, 00:12:48
B 192.168.199.0/24 [200/0] via 1.1.1.1, 00:12:48
B 192.168.200.0/24 [200/0] via 1.1.1.1, 00:12:48
B 192.168.250.0/24 [200/0] via 1.1.1.1, 00:12:49
B 192.168.50.0/24 [20/0] via 192.168.1.205, 00:12:51
192.168.1.0/30 is subnetted, 7 subnets
B 192.168.1.200 [20/0] via 192.168.1.205, 00:12:51
C 192.168.1.204 is directly connected, Ethernet1/2
C 192.168.1.192 is directly connected, Ethernet1/0
C 192.168.1.196 is directly connected, Ethernet1/1
B 192.168.1.216 [200/0] via 1.1.1.1, 00:12:48
O 192.168.1.220 [110/20] via 192.168.1.193, 00:13:30, Ethernet1/0
B 192.168.1.212 [200/0] via 1.1.1.1, 00:12:49
B 192.168.100.0/24 [200/0] via 1.1.1.1, 00:12:48
B 192.168.192.0/21 [200/0] via 1.1.1.1, 00:12:48
R4#sh ip bgp summary
BGP router identifier 3.3.3.3, local AS number 100
BGP table version is 18, main routing table version 18
17 network entries using 1989 bytes of memory
17 path entries using 884 bytes of memory
5/4 BGP path/bestpath attribute entries using 620 bytes of memory
3 BGP AS-PATH entries using 72 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 3565 total bytes of memory
BGP activity 17/0 prefixes, 17/0 paths, scan interval 60 secs
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
1.1.1.1 4 100 19 17 18 0 0 00:13:37 14
2.2.2.2 4 100 16 17 18 0 0 00:13:25 0
192.168.1.205 4 400 17 19 18 0 0 00:13:30 3
R5#sh ip bgp
BGP table version is 18, local router ID is 192.168.75.1
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
*> 192.168.1.200/30 0.0.0.0 0 32768 i
*> 192.168.1.212/30 192.168.1.206 0 100 300 i
*> 192.168.1.216/30 192.168.1.206 0 100 200 i
*> 192.168.50.0 0.0.0.0 0 32768 i
*> 192.168.75.0 0.0.0.0 0 32768 i
*> 192.168.100.0 192.168.1.206 0 100 200 i
*> 192.168.192.0 192.168.1.206 0 100 200 i
*> 192.168.192.0/21 192.168.1.206 0 100 200 i
*> 192.168.193.0 192.168.1.206 0 100 200 i
*> 192.168.194.0 192.168.1.206 0 100 200 i
*> 192.168.195.0 192.168.1.206 0 100 200 i
*> 192.168.196.0 192.168.1.206 0 100 200 i
*> 192.168.197.0 192.168.1.206 0 100 200 i
*> 192.168.198.0 192.168.1.206 0 100 200 i
*> 192.168.199.0 192.168.1.206 0 100 200 i
*> 192.168.200.0 192.168.1.206 0 100 200 i
*> 192.168.250.0 192.168.1.206 0 100 300 i
R5#sh ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
B 192.168.192.0/24 [20/0] via 192.168.1.206, 00:13:03
B 192.168.193.0/24 [20/0] via 192.168.1.206, 00:13:03
B 192.168.194.0/24 [20/0] via 192.168.1.206, 00:13:03
C 192.168.75.0/24 is directly connected, Loopback1
B 192.168.195.0/24 [20/0] via 192.168.1.206, 00:13:03
B 192.168.196.0/24 [20/0] via 192.168.1.206, 00:13:03
B 192.168.197.0/24 [20/0] via 192.168.1.206, 00:13:03
B 192.168.198.0/24 [20/0] via 192.168.1.206, 00:13:03
B 192.168.199.0/24 [20/0] via 192.168.1.206, 00:13:03
B 192.168.200.0/24 [20/0] via 192.168.1.206, 00:13:03
B 192.168.250.0/24 [20/0] via 192.168.1.206, 00:13:34
C 192.168.50.0/24 is directly connected, Loopback0
192.168.1.0/30 is subnetted, 4 subnets
C 192.168.1.200 is directly connected, Loopback3
C 192.168.1.204 is directly connected, Ethernet1/0
B 192.168.1.216 [20/0] via 192.168.1.206, 00:13:04
B 192.168.1.212 [20/0] via 192.168.1.206, 00:13:35
B 192.168.100.0/24 [20/0] via 192.168.1.206, 00:13:04
B 192.168.192.0/21 [20/0] via 192.168.1.206, 00:13:04