WB1 7.14 BGP Redistribute Internal

• Configure R1, R3, R4, and R6 in AS 100.
• R4 and R6 should peer with BB3 and BB1 respectively, who are in AS 54.
• R1 should peer with R3, R4, and R6 as a route reflector.
• Configure R4 and R6 to advertise the network 155.X.0.0/16 to AS 54.
• Configure BGP to IGP redistribution on R3 so that all internal devices have reachability to the prefixes learned from AS 54.

Configuration

R1:
router eigrp 100
distance eigrp 90 201
(R1從iBGP學到AS54的路由，AD200，透過R3的bgp redistribute-internal，每一台eigrp路由器都學到AS54的AD為170，就會造成R1的BGP路由表產生RIB-failure(17)，唯一的方法是把eigrp的external AD值改的比iBGP要大)
!
router bgp 100
neighbor 155.1.146.4 remote-as 100
neighbor 155.1.146.6 remote-as 100
neighbor 155.1.13.3 remote-as 100
neighbor 155.1.146.4 route-reflector-client
neighbor 155.1.146.6 route-reflector-client
neighbor 155.1.13.3 route-reflector-client

R2:
no router bgp 200

R3:
router eigrp 100
redistribute bgp 100 metric 100000 1000 255 1 1500
!
router bgp 100
neighbor 155.1.13.1 remote-as 100
neighbor 155.1.13.1 route-map SET_NEXT_HOP_FROM_R1 in
bgp redistribute-internal
!
route-map SET_NEXT_HOP_FROM_R1 permit 10
set ip next-hop 155.1.13.1
(避免往AS54的路由，遞迴查詢是155.1.146.4卻是走SW1(via EIGRP)->R3->SW1->Loop，所以需要改bgp next-hop為R1)

iBGP learned prefixes are not automatically redistributed into IGP when you issue the statement
redistribute bgp under any IGP process on the router – only eBGP prefixes are propagated. In order to make iBGP redistribution possible, you need an additional statement configured under the BGP process: bgp redistribute internal.

R4:
no router bgp 100
router bgp 100
neighbor 155.1.146.1 remote-as 100
neighbor 155.1.146.1 next-hop-self
neighbor 204.12.1.254 remote-as 54
network 155.1.146.0 mask 255.255.255.0
aggregate-address 155.1.0.0 255.255.0.0

R6:
router bgp 100
neighbor 155.1.146.1 remote-as 100
neighbor 155.1.146.1 next-hop-self
neighbor 54.1.1.254 remote-as 54
network 155.1.146.0 mask 255.255.255.0
aggregate-address 155.1.0.0 255.255.0.0