Brocade BigIron RX Series Configuration Guide - Manual (Page 946)

868 BigIron RX Series Configuration Guide
53-1002484-04
Configuring route reflection parameters
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NOTE
If the cluster contains more than one route reflector, you need to configure the same cluster ID
on all the route reflectors in the cluster. The cluster ID helps route reflectors avoid loops within
the cluster.
• A route reflector is an IGP router configured to send BGP route information to all the clients
(other BGP4 routers) within the cluster. Route reflection is enabled on all Brocade BGP4
routers by default but does not take effect unless you add route reflector clients to the router.
• A route reflector client is an IGP router identified as a member of a cluster. You identify a
router as a route reflector client on the router that is the route reflector, not on the client. The
client itself requires no additional configuration. In fact, the client does not know that it is a
route reflector client. The client just knows that it receives updates from its neighbors and
does not know whether one or more of those neighbors are route reflectors.
NOTE
Route reflection applies only among IBGP routers within the same AS. You cannot configure a
cluster that spans multiple ASs.
Figure 26.4 shows an example of a route reflector configuration. In this example, two devices are
configured as route reflectors for the same cluster. The route reflectors provide redundancy in case
one of the reflectors becomes unavailable. Without redundancy, if a route reflector becomes
unavailable, its clients are cut off from BGP4 updates.
AS1 contains a cluster with two route reflectors and two clients. The route reflectors are fully
meshed with other BGP4 routers, but the clients are not fully meshed. They rely on the route
reflectors to propagate BGP4 route updates.
FIGURE 125 Example route reflector configuration
Support for RFC 2796
Route reflection is based on RFC 2796. This updated RFC helps eliminate routing loops that are
possible in some implementations of the older specification, RFC 1966.
Route
Reflector 1
Route
Reflector 2
Route
Reflector
Client 1
10.0.1.0
Route
Reflector
Client 2
10.0.2.0
EBGP
IBGP
IBGP
IBGP
AS 1 AS 2
Cluster 1