Symptom
Origin AS in FIB and RIB are different, which may result wrong NF export value.
N7K# show ip route 192.168.0.2 detail
192.168.0.2/24, ubest/mbest: 1/0
*via 192.168.100.1, [20/0], 01:29:48, bgp-100, external, tag 2
client-specific data: 23
recursive next hop: 192.168.100.1/32
extended route information: BGP origin AS 1 BGP peer AS 2 <--- origin AS 1
N7K# show forwarding route 192.168.0.2 detail
Prefix 192.168.0.2/24, No of paths: 1, Update time: Fri May 24 11:43:21 2013
Vobj id: 15 orig_as: 3 peer_as: 2 rnh: 192.168.100.1 <--- orig_as: 3
192.168.100.1 Ethernet9/13 DMAC: 000c.2982.8c93
packets: 0 bytes: 0
Conditions
This issue happens when some BGP routes have same next-hop.
N7K# sh ip bgp
BGP routing table information for VRF default, address family IPv4 Unicast
BGP table version is 223, local router ID is 20.0.0.1
Status: s-suppressed, x-deleted, S-stale, d-dampened, h-history, *-valid, >-best
Path type: i-internal, e-external, c-confed, l-local, a-aggregate, r-redist
Origin codes: i - IGP, e - EGP, ? - incomplete, | - multipath
Network Next Hop Metric LocPrf Weight Path
*>e192.168.0.1/24 192.168.100.1 0 2 4 5 i
*>e192.168.0.2/24 192.168.100.1 0 2 4 6 7 7 7 7 7 1 i
*>e192.168.0.3/24 192.168.100.1 0 2 4 6 7 7 7 7 7 1 i
*>e192.168.0.4/24 192.168.100.1 0 2 4 6 7 7 7 7 7 1 i
*>e192.168.0.5/23 192.168.100.1 0 2 4 8 3 i
*>e192.168.0.6/23 192.168.100.1 0 2 4 8 3 i
*>e192.168.0.7/23 192.168.100.1 0 2 4 8 3 i
*>e192.168.0.8/23 192.168.100.1 0 2 4 8 3 i
In this case, orig_as for all the routes above will be same on FIB.
The same value will be selected from one of 5, 1 and 3.
