实验：
r4:
int lo0
ip add 4.4.4.4 255.255.255.0
int s1/1
ip add 24.1.1.4 255.255.255.0
no sh
r2:
int lo0
ip add 2.2.2.2 255.255.255
int s/1
ip add 24.1.1.2 255.255.255.0
no sh
int s/10
ip add 12.1.1.2 255.255.255.0
no sh
r1:
int lo0
ip add 1.1.1.1 255.255.255.0
int s1/0
ip add 12.1.1.1 255.255.255.0
no sh
int s1/2
no sh
ip add 13.1.1.1 255.255.255.0
r3:
int lo0
ip add 3.3.3.3 255.255.255.0
int s1/2
ip add 13.1.1.3 255.255.255.0
no sh
int s1/1
ip add 35.1.1.3 255.255.255.0
no sh
r5:
int lo0
ip add 5.5.5.5 255.255.255.0
int s1/1
ip add 35.1.1.5 255.255.255.0
no sh
r2:
router eigrp 100
no au
net 2.0.0.0
net 12.0.0.0
r1:
router eigrp 100
no au
net 12.0.0.0
net 1.0.0.0
net 13.0.0.0
r3:
router eigrp 100
no au
net 3.0.0.0
net 13.0.0.0
r2:
router bgp 123
bgp router-id 2.2.2.2
no au
no syn
neighbor 1.1.1.1 remote-as 123
neighbor 1.1.1.1 update-souce lo0
neighbor 3.3.3.3 remote-as 123
neighbor 3.3.3.3 update-souce lo0
r3:
router bgp 123
bgp router-id 3.3.3.3
no auto
no syn
neighbor 2.2.2.2 remote-as 123
neighbor 2.2.2.2 up lo0
neighbro 1.1.1.1 remote-as 123
neighbor 1.1.1.1 update-souce lo0
r1:
router bgp 123
no auto
bgp router-id 1.1.1.1
no au
no syn
neighbor ibgp peer-group
neighbor ibgp remote-as 123
neighbor ibgp up lo0
neighbor 2.2.2.2 peer-group ibgp
neighbor 3.3.3.3 peer-group ibgp
r4:
router bgp 4
bgp route-id 4.4.4.4
no auto
no syn
neighbor 23.1.1.2 remote-as 123
r2:
router bgp 123
neighbor 24.1.1.4 remote-as 4
r3:
router bgp 123
neighbor 5.5.5.5 remote-as 5
neighbor 5.5.5.5 updata-souce lo0
neighbor 5.5.5.5 ebpg-multihop
r5:
router bgp 5
bgp router-id 5.5.5.5
neighbor 3.3.3.3 remote-as 123
neighbor 3.3.3.3 up lo0
neighbor 3.3.3.3 ebpg-multihop
r3:
ip route 5.5.5.0 255.255.255.0 35.1.1.5
r5:
ip route 3.3.3.0 255.255.255.0 35.1.1.3
