Cisco ASR 9000 Series Configuration Manual page 90

BGP Accept Own
Accept Own Configuration Example
In this configuration example:
• PE11 is configured with Customer VRF and Service VRF.
• OSPF is used as the IGP.
• VPNv4 unicast and VPNv6 unicast address families are enabled between the PE and RR neighbors and
IPv4 and IPv6 are enabled between PE and CE neighbors.
The Accept Own configuration works as follows:
1 CE1 originates prefix X.
2 Prefix X is installed in customer VRF as (RD1:X).
3 Prefix X is advertised to IntraAS-RR11 as (RD1:X, RT1).
4 IntraAS-RR11 advertises X to InterAS-RR1 as (RD1:X, RT1).
5 InterAS-RR1 attaches RT2 to prefix X on the inbound and ACCEPT_OWN community on the outbound
and advertises prefix X to IntraAS-RR31.
6 IntraAS-RR31 advertises X to PE11.
7 PE11 installs X in Service VRF as (RD2:X,RT1, RT2, ACCEPT_OWN).
Remote PE: Handling of Accept Own Routes
Remote PEs (PEs other than the originator PE), performs bestpath calculation among all the comparable
routes. The bestpath algorithm has been modified to prefer an Accept Own path over non-Accept Own path.
The bestpath comparison occurs immediately before the IGP metric comparison. If the remote PE receives
an Accept Own path from route-reflector 1 and a non-Accept Own path from route-reflector 2, and if the paths
are otherwise identical, the Accept Own path is preferred. The import operates on the Accept Own path.
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.1.x
62
Implementing BGP
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