Owner's Manual

Chapter 26. BGP | 703
NETGEAR 8800 User Manual
entry two {
if {
nlri 192.168.34.0/24;
} then {
extended-community set "rt:10.45.92.168:300";
extended-community add "rt:10.203.100.200:40 soo:100:60000";
extended-community delete "rt:65001:10000 soo:72.192.34.10:70";
permit;
}
}
A BGP route 192.168.34.128/25 is received with extended community attribute rt:4567:100
soo:192.168.34.128
. When the above policy entry is applied to the route's extended
community attribute, the following is true:
• After applying the 1st set (community set "rt:10.45.92.168:300"), the route's community
becomes
rt:10.45.92.168:300.
• After applying the 2nd set (community add "rt:10.203.100.200:40 soo:100:60000"), the
community becomes
rt:10.45.92.168:300 rt:10.203.100.200:40 soo:100:60000.
• After applying the 3rd set (community delete "rt:65001:10000 soo:72.192.34.10:70"),
the community becomes
rt:10.45.92.168:300 rt:10.203.100.200:40 soo:100:60000.
Note that this delete statement has no effect as none of the communities in the delete
statement are present in the community attribute.
Extended Communities and BGP Route Aggregation
When BGP routes are aggregated with the as-match or as-set CLI option, all the component
route's extended community attributes are aggregated and the resulting aggregated
extended community attributes are attached to the aggregate network.
Aggregation of several extended community attributes is simply the set union of all the
extended communities from all of the aggregated routes.
Multiprotocol BGP
Multiprotocol BGP (MBGP) is an enhanced BGP that carries IP multicast routes. BGP carries
two sets of routes: one set for unicast routing and one set for multicast routing. This allows
BGP to have non-congruent topologies for IPv4 Unicast and IPv4 Multicast networks. The
routes associated with multicast routing are used by the Protocol Independent Multicast
(PIM) to build data distribution trees.
BGP Features
This section describes the following configurable BGP features supported by XCM8800:
• Route Reflectors on page 704
• Route Confederations on page 706
• Route Aggregation on page 710