Switch 7700 Configuration Guide, v2

BGP 127
Configuring BGP Route Summarization
The CIDR supports route summarization. There are two modes of BGP route
summarization: summary automatic and aggregate. The summary automatic
is the summary of the BGP subnet routes. After the configuration of the summary
automatic, the BGP will not be able to receive subnets imported by the IGP; the
aggregate is the aggregation of the BGP local routes. A series of parameters can
be configured in the aggregate. In general, the preference of the aggregation is
higher than that of the summarization.
Perform the following configuration in the BGP view:
By default, the BGP will not perform local route aggregation.
Configuring an BGP Route Reflector
To ensure the interconnection between IBGP peers, it is necessary to establish a
fully connected network. In some networks, there are large numbers of IBGP
peers, and the internal BGP network becomes very large, consequently the costs
to establish fully meshed network are very large so new peer technology is
necessary. The basic idea of route reflector conception is to specify a centralized
router as the focus of the internal session. Multiple BGP routers can peer one
central point, and then multiple route reflectors will peer again.
Route reflector is the centralized point of other routers, and other routers are
called the clients. The client is the peer of the route reflector and switching the
routing information with it. The route reflector will reflect the information in order
among the clients.
In Figure 12, Router A receives an update packet from the external peer and
transmits it to Router C. Router C is a route reflector with two peer clients: Router
A and Router B.
Router C reflects the update packet from client Router A to client Router B. Under
such configuration, the peer session between Router A and Router B is actually
eliminated because the route reflector will transfer the BGP information to Router
B.
Table 108 Configuring BGP Route Summarization
Operation Command
Configure the summary automatic function of
the subnet routes
summary automatic
Cancel the summary automatic function of
the subnet routes
undo summary automatic
Configure local route aggregation function aggregate address mask [ as-set ] [
detail-suppressed ] [ suppress-policy
route-policy-name ] [ origin-policy
route-policy-name ] [ attribute-policy
route-policy-name ]
Cancel local route aggregation function undo aggregate address mask [ as-set ] [
detail-suppressed ] [ suppress-policy
route-policy-name ] [ origin-policy
route-policy-name ] attribute-policy
route-policy-name ]