R1(config)#int
f0/0
R1(config-if)#ip
add 10.1.12.1 255.255.255.0
R1(config-if)#no
sh
R1(config)#int
lo0
R1(config-if)#ip
add 1.1.1.1 255.255.255.255
R1(config-if)#exit
R1(config)#router
bgp 1
R1(config-router)#neighbor
10.1.12.2 remote-as 2
R1(config-router)#neighbor
10.1.12.2 ebgp-multihop 3
R1(config-router)#neighbor
10.1.12.2 update-source loopback 0
R1(config-router)#network
1.1.1.1 mask 255.255.255.255
R1(config-router)#end
R2(config)#int
f0/0
R2(config-if)#ip
add 10.1.12.2 255.255.255.0
R2(config-if)#no
sh
R2(config)#int
f1/0
R2(config-if)#ip
add 10.1.23.2 255.255.255.0
R2(config-if)#no
sh
R2(config)#int
lo0
R2(config-if)#ip
add 2.2.2.2 255.255.255.255
R2(config-if)#exit
R2(config)#router
bgp 2
R2(config-router)#nei
10.1.12.1 remote-as 1
R2(config-router)#nei
10.1.23.3 remote-as 3
R2(config-router)#net
2.2.2.2 mask 255.255.255.255
R2(config-router)#end
R3(config)#int
f0/0
R3(config-if)#ip
add 10.1.23.3 255.255.255.0
R3(config-if)#no
sh
R3(config)#int
f1/0
R3(config-if)#ip
add 10.1.34.3 255.255.255.0
R3(config-if)#no
sh
R3(config)#int
lo0
R3(config-if)#ip
add 3.3.3.3 255.255.255.255
R3(config-if)#exit
R3(config)#router
bgp 3
R3(config-router)#nei
10.1.23.2 remote-as 2
R3(config-router)#nei
10.1.34.4 remote-as 4
R3(config-router)#net
3.3.3.3 mask 255.255.255.255
R3(config-router)#end
R4(config)#int
f0/0
R4(config-if)#ip
add 10.1.34.4 255.255.255.0
R4(config-if)#no
sh
R4(config)#int
lo0
R4(config-if)#ip
add 4.4.4.4 255.255.255.255
R4(config-if)#exit
R4(config)#router
bgp 4
R4(config-router)#nei
10.1.34.3 remote-as 3
R4(config-router)#net
4.4.4.4 mask 255.255.255.255
R4(config-router)#end
R2#sh ip bgp
BGP table version is 5, local
router ID is 2.2.2.2
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
*> 1.1.1.1/32 10.1.12.1 0 0 1 i
*> 2.2.2.2/32 0.0.0.0 0
2768 i
*> 3.3.3.3/32 10.1.23.3 0 0 3 i
*> 4.4.4.4/32 10.1.23.3 0 3 4 i
R2#sh run | s bgp
router bgp 2
no synchronization
bgp log-neighbor-changes
network 2.2.2.2 mask 255.255.255.255
neighbor 10.1.12.1 remote-as 1
neighbor 10.1.23.3 remote-as 3
no auto-summary
R2#sh ip bgp summ
BGP router identifier
2.2.2.2, local AS number 2
BGP table version is 5, main
routing table version 5
4 network entries using 468
bytes of memory
4 path entries using 208
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 1368 total bytes of
memory
BGP activity 4/0 prefixes,
4/0 paths, scan interval 60 secs
Neighbor V
AS MsgRcvd MsgSent
TblVer InQ OutQ Up/Down State/PfxRcd
10.1.12.1 4 1 17 19
5 0 0 00:13:23 1
10.1.23.3 4 3 16 19
5 0 0 00:09:33 2
R2#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
1.0.0.0/32 is subnetted, 1 subnets
B 1.1.1.1 [20/0] via 10.1.12.1, 00:13:51
2.0.0.0/32 is subnetted, 1 subnets
C 2.2.2.2 is directly connected, Loopback0
3.0.0.0/32 is subnetted, 1 subnets
B 3.3.3.3 [20/0] via 10.1.23.3, 00:08:01
4.0.0.0/32 is subnetted, 1 subnets
B 4.4.4.4 [20/0] via 10.1.23.3, 00:07:00
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.12.0 is directly connected,
FastEthernet0/0
C 10.1.23.0 is directly connected,
FastEthernet1/0
R2#sh tcp bri
TCB Local Address Foreign Address (state)
64EDDC80 10.1.23.2.42087 10.1.23.3.179 ESTAB
64EDED04 10.1.12.2.179 10.1.12.1.45753 ESTAB
R1#sh ip bgp
BGP table version is 5, local
router ID is 1.1.1.1
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
*> 1.1.1.1/32 0.0.0.0 0
32768 i
*> 2.2.2.2/32 10.1.12.2 0 0 2 i
*> 3.3.3.3/32 10.1.12.2 0 2 3 i
*> 4.4.4.4/32 10.1.12.2 0 2 3 4 i
R3#sh ip bgp
BGP table version is 5, 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
*> 1.1.1.1/32 10.1.23.2 0 2 1 i
*> 2.2.2.2/32 10.1.23.2 0 0 2 i
*> 3.3.3.3/32 0.0.0.0 0
32768 i
*> 4.4.4.4/32 10.1.34.4 0 0 4 i
R4#sh ip bgp
BGP table version is 5, local
router ID is 4.4.4.4
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
*> 1.1.1.1/32 10.1.34.3 0 3 2 1 i
*> 2.2.2.2/32 10.1.34.3 0 3 2 i
*> 3.3.3.3/32 10.1.34.3 0 0 3 i
*> 4.4.4.4/32 0.0.0.0 0
32768 i