Chapter 10: BGP Configuration Guide
138
DIGITAL GIGAswitch/Router User Reference Manual
Notes on Using Route Reflection
•
Two types of route reflection are supported:
–
By default, all routes received by the route reflector from a client are sent to all
internal peers (including the client’s group, but not the client itself).
–
If the
no-client-reflec
t option is enabled, routes received from a route reflection
client are sent only to internal peers that are not members of the client's group. In
this case, the client's group must itself be fully meshed.
In either case, all routes received from a non-client internal peer are sent to all route
reflection clients.
•
Typically, a single router acts as the reflector for a cluster of clients. However, for
redundancy, two or more may also be configured to be reflectors for the same cluster.
In this case, a cluster ID should be selected to identify all reflectors serving the cluster,
using the
clusterid
option. Gratuitous use of multiple redundant reflectors is not
advised, since it can lead to an increase in the memory required to store routes on the
redundant reflectors’ peers.
•
No special configuration is required on the route reflection clients. From a client's
perspective, a route reflector is simply a normal IBGP peer. Any BGP version 4 speaker
can be a reflector client.
•
It is necessary to export routes from the local AS into the local AS when acting as a
route reflector.
To accomplish this, routers GSR10 and GSR11 have the following line in their
configuration files:
•
If the cluster ID is changed, all BGP sessions with reflector clients will be dropped and
restarted.
ip-router policy redistribute from-proto bgp source-as 64901 to-
proto bgp target-as 64901
