Riverstone Networks WICT1-12 - Manual (Page 277)

Riverstone Networks RS Switch Router User Guide Release 8.0 16-19
BGP Configuration Guide BGP Configuration Examples
The following lines on the Cisco router set up IBGP peering with router R6.
16.3.3 EBGP Multihop Configuration Example
EBGP Multihop refers to a configuration where external BGP neighbors are not connected to the same subnet. Such
neighbors are logically, but not physically connected. For example, BGP can be run between external neighbors across
non-BGP routers. Some additional configuration is required to indicate that the external peers are not physically
attached.
This sample configuration shows External BGP peers, R1 and R4, which are not connected to the same subnet.
Figure 16-4 Sample EBGP configuration (multihop)
router bgp 64801
!
! Disable synchronization between BGP and IGP
!
no synchronization
neighbor 172.23.1.26 remote-as 64801
!
! Allow internal BGP sessions to use any operational interface for TCP
! connections
!
neighbor 172.23.1.26 update-source Loopback0
Physical Link
Legend:
Peering Relationship
R
1
16.122.128.1/16
R
3
AS-64800
AS-64801
R
4
R 2
16.122.128.3/16
17.122.128.3/16
17.122.128.4/16
18.122.128.3/16
18.122.128.2/16