Configuring BGP Route Reflectors
BGP route reflectors are intended for ASs with a large mesh; they reduce the amount of BGP control
traffic.
With route reflection configured properly, IBGP routers are not fully meshed within a cluster but all
receive routing information.
Configure clusters of routers where one router is a concentration router and the others are clients who
receive their updates from the concentration router.
To configure a route reflector, use the following commands.
• Assign an ID to a router reflector cluster.
CONFIG-ROUTER-BGP mode
bgp cluster-id cluster-id
You can have multiple clusters in an AS.
• Configure the local router as a route reflector and the neighbor or peer group identified is the route
reflector client.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | peer-group-name} route-reflector-client
When you enable a route reflector, the system automatically enables route reflection to all clients. To
disable route reflection between all clients in this reflector, use the no bgp client-to-client
reflection command in CONFIGURATION ROUTER BGP mode. All clients must be fully meshed
before you disable route reflection.
To view a route reflector configuration, use the show config command in CONFIGURATION ROUTER
BGP mode or the
show running-config bgp in EXEC Privilege mode.
Aggregating Routes
The Dell Networking OS provides multiple ways to aggregate routes in the BGP routing table. At least one
specific route of the aggregate must be in the routing table for the configured aggregate to become
active.
To aggregate routes, use the following command.
AS_SET includes AS_PATH and community information from the routes included in the aggregated route.
• Assign the IP address and mask of the prefix to be aggregated.
CONFIG-ROUTER-BGP mode
aggregate-address ip-address mask [advertise-map map-name] [as-set]
[attribute-map map-name] [summary-only] [suppress-map map-name]
Example of Viewing Aggregated Routes
In the show ip bgp command, aggregates contain an ‘a’ in the first column (shown in bold) and routes
suppressed by the aggregate contain an ‘s’ in the first column.
Dell#show ip bgp
BGP table version is 0, local router ID is 10.101.15.13
Status codes: s suppressed, d damped, h history, * valid, > best
Path source: I - internal,
a - aggregate, c - confed-external, r -
Border Gateway Protocol IPv4 (BGPv4)
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