Default Originate; Neighbor Export - Cisco ASR 9000 Series Routing Configuration Manual

Implementing Routing Policy
The following policy sets dampening values for BGP IPv4 unicast routes. Those routes that are more specific
than a /25 take longer to recover after they have been dampened than routes that are less specific than /25.
route-policy sample_damp
if destination in (0.0.0.0/0 ge 25) then
set dampening halflife 30 others default
else
set dampening halflife 20 others default
endif
end-policy
router bgp 2
address-family ipv4 unicast
bgp dampening route-policy sample_damp
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Default Originate

The default originate attach point allows the default route (0.0.0.0/0) to be conditionally generated and
advertised to a peer, based on the presence of other routes. It accomplishes this configuration by evaluating
the associated policy against routes in the Routing Information Base (RIB). If any routes pass the policy, the
default route is generated and sent to the relevant peer.
The following policy generates and sends a default-route to the BGP neighbor 10.0.0.1 if any routes that match
10.0.0.0/8 ge 8 le 32 are present in the RIB.
route-policy sample-originate
if rib-has-route in (10.0.0.0/8 ge 8 le 32) then
endif
end-policy
router bgp 2
neighbor 10.0.0.1
remote-as 3
address-family ipv4 unicast
default-originate route-policy sample-originate
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Neighbor Export

The neighbor export attach point selects the BGP routes to send to a given peer or group of peers. The routes
are selected by running the set of possible BGP routes through the associated policy. Any routes that pass the
policy are then sent as updates to the peer or group of peers. The routes that are sent may have had their BGP
attributes altered by the policy that has been applied.
The following policy sends all BGP routes to neighbor 10.0.0.5. Routes that are tagged with any community
in the range 2:100 to 2:200 are sent with a MED of 100 and a community of 2:666. The rest of the routes are
sent with a MED of 200 and a community of 2:200.
route-policy sample-export
if community matches-any (2:[100-200]) then
set med 100
set community (2:666)
else
set med 200
pass
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.3.x
Attach Points
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