Information Technology Reference
In-Depth Information
Because of some similarities between iBGP full mesh and route reflection (for example,
neither has AS subdivision), many of the procedures described in this case study are similar
to those in Case Study 2. Thus, detailed discussions in some steps are omitted for brevity.
For completeness, all necessary steps are still retained.
Starting Configurations
Although some of the configurations were presented in Case Study 1 in the section “Final
BGP Configurations,” the complete BGP configurations for all the routers are presented
here for reference in Examples 8-48 through 8-55.
The BGP next hop is reset on R1 so that the external prefix can be reached in AS 100. The
other way to accomplish the reachability is to put the inter-AS link in IS-IS and configure
passive interface on the link, as shown in Example 8-48.
Example 8-48
BGP Configurations on R1
router bgp 100
no synchronization
bgp router-id 192.168.100.1
bgp log-neighbor-changes
neighbor Internal peer-group
neighbor Internal remote-as 100
neighbor Internal update-source Loopback0
neighbor Internal next-hop-self
neighbor Clients peer-group
neighbor Clients remote-as 100
neighbor Clients update-source Loopback0
neighbor Clients route-reflector-client
neighbor Clients next-hop-self
neighbor 192.168.18.8 remote-as 200
neighbor 192.168.100.2 peer-group Internal
neighbor 192.168.100.3 peer-group Clients
neighbor 192.168.100.4 peer-group Internal
neighbor 192.168.100.5 peer-group Internal
no auto-summary
Configure route reflection on R1 and R2, with R3 as the only client. All core routers (RRs)
are fully meshed. (See Example 8-49.)
Example 8-49
BGP Configurations on R2
router bgp 100
no synchronization
bgp router-id 192.168.100.2
bgp log-neighbor-changes
neighbor Internal peer-group
neighbor Internal remote-as 100
neighbor Internal update-source Loopback0
