Bgp Accept Own - Cisco ASR 9000 Series Routing Configuration Manual

Implementing BGP
Role change timestamp
Current Role
No. of times Eod received : 2
Eod received
No. of Tables
No. of Converged Tables
No. of Deleted Tables
No. of Bcdl Subscribed Tables :
No. of Marked Tables
The number of VRFs provisioned on the line card (o) is derived from the "No. Of Tables" field in the show
cef tables summary location 0/0/cpu0. This provides the tables specific to the Linecard 0/0/cpu0.
The routes per VRF (R) can be found using the show cef tables location node-id command.
RP/0/RSP0/CPU0:router#show cef tables location 0/1/CPU0
Sat Apr
Codes:
Table
default
**nVSatellite
cdn
oir
vrf1
For the vrf "vrf1" the total routes is in the "T" column which is 11. So if the number of routes per VRF are
not the same for all vrfs then total of "routes in all non-default" vrfs will have to be calculated and divided by
the number of VRFs, to arrive at the Average Routes per VRF.
The ratio of SVD local: total routes (x) can be found using the number of SVD Local Routes and the number
of Total Routes for a given VRF. For example, in the above sample output of show cef tables location
0/1/CPU0, in the L column, the number represents the Local Routes, and in the T column number represents
Total routes in that Vrf. So ratio of L column to T column number will give the ratio for a given vrf. Again
if the ratio is not same for all vrfs, it will have to be averaged out over all vrfs.
The number of VRFs dependant on directly provisioned VRFs (Y) will have to manually calculated because
it depends on the router configuration. For example, if route import targets in Dependant VRF import from
routes exported by other VRFs. A VRF is dependant if it depends on a nexthops being in some other VRF
which is directly provisioned. There is no show command to automatically calculate Y, since it depends
completely on the way router is configured to import routes in various VRFs.

BGP Accept Own

The BGP Accept Own feature enables handling of self-originated VPN routes, which a BGP speaker receives
from a route-reflector (RR). A "self-originated" route is one which was originally advertized by the speaker
itself. As per BGP protocol [RFC4271], a BGP speaker rejects advertisements that were originated by the
speaker itself. However, the BGP Accept Own mechanism enables a router to accept the prefixes it has
advertised, when reflected from a route-reflector that modifies certain attributes of the prefix. A special
community called ACCEPT-OWN is attached to the prefix by the route-reflector, which is a signal to the
receiving router to bypass the ORIGINATOR_ID and NEXTHOP/MP_REACH_NLRI check. Generally, the
BGP speaker detects prefixes that are self-originated through the self-origination check (ORIGINATOR_ID,
NEXTHOP/MP_REACH_NLRI) and drops the received updates. However, with the Accept Own community
present in the update, the BGP speaker handles the route.
: Apr
: Core
: Apr
:
:
:
:
6 01:22:32.471 UTC
L - SVD Local Routes, R - SVD Remote Routes
T - Total Routes
C - Table Converged, D - Table Deleted
M - Table Marked, S - Table Subscribed
Table ID
0xe0000000
0xe0000010
0xe0000011
0xe0000012
0xe0000013
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.3.x
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3 07:21:46.980
106
106
0
106
0
L R
9 3
1 0
0 0
0 0
3 1
BGP Accept Own
T C D M S
23 Y N N Y
6 Y N N Y
5 Y N N Y
5 Y N N Y
11 Y N N Y
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