기존랩에 추가하여
Confederation 설정

R9
router ospf 1
network 1.1.19.0 0.0.0.255 area 0
network 9.9.9.0 0.0.0.255 area 0
router bgp 65000
bgp confederation identifier 300 #confederation 설정
network 9.9.9.0 mask 255.255.255.0
neighbor 3.3.49.2 remote-as 10
neighbor 10.10.10.10 remote-as 65000
neighbor 10.10.10.10 update-source Loopback0
R10
router ospf 1
network 1.1.11.0 0.0.0.255 area 0
network 1.1.19.0 0.0.0.255 area 0
network 10.10.10.0 0.0.0.255 area 0
router bgp 65000
bgp confederation identifier 300
network 10.10.10.0 mask 255.255.255.0
neighbor 9.9.9.9 remote-as 65000
neighbor 9.9.9.9 update-source Loopback0

R9
interface Loopback0
ip ospf network point-to-point
interface GigabitEthernet1/0
ip ospf network point-to-point
R10
interface Loopback0
ip ospf network point-to-point
interface GigabitEthernet1/0
ip ospf network point-to-point
loopback interface도 p2p 설정 해줘야 네트워크 정보를 정확히 가져옴
R4
router bgp 10
neighbor 3.3.49.1 remote-as 300
R4
sh ip bgp
R9의 Path는 65000 이 아닌 300으로 보임
AS 300을 통해 9.9.9.9 이동 가능
R10
sh ip bgp
경로가 괄호로 표시 AS300 이지만 65001로 표시
R10과 R11 설정

R11 기본 설정
interface GigabitEthernet0/0
ip ospf network point-to-point
interface Loopback0
ip ospf network point-to-point
router ospf 1
network 1.1.11.0 0.0.0.255 area 0
network 11.11.11.0 0.0.0.255 area 0
router bgp 65001
bgp confederation identifier 300
network 11.11.11.0 mask 255.255.255.0
neighbor 3.3.15.2 remote-as 20 #R5 이웃 설정
R10
router bgp 65000
bgp confederation identifier 300
bgp confederation peers 65001
neighbor 11.11.11.11 remote-as 65001
neighbor 11.11.11.11 update-source Loopback0
neighbor 11.11.11.11 ebgp-multihop 2 #ebg 홉수 2로 설정
기본 eBGP 설정으로는 세션이 설정되지 않음
ebgp-multihop을 사용해 허용할 홉 수를 늘려 세션을 설정
R11
router bgp 65001
bgp confederation peers 65000
neighbor 10.10.10.10 remote-as 65000
neighbor 10.10.10.10 update-source Loopback0
neighbor 10.10.10.10 ebgp-multihop 2
neighbor 10.10.10.10 ebgp-multihop 2 #ebg 홉수 2로 설정

R9
neighbor 10.10.10.10 next-hop-self
R10
neighbor 9.9.9.9 next-hop-self
R11
neighbor 10.10.10.10 next-hop-self
R10
sh ip bgp
next hop이 9.9.9.9 or 11.11.11.11인것을 확인할 수 있음
