12-06-2010 01:50 PM - edited 03-04-2019 10:42 AM
so I have this output, the "local" route is appearing in my routing table via eigrp. 10.33.254.20 is not a bgp neigh, and 10.40.33.4 is this routers loopback. The primary route should be via bgp. Those routes are being redistirbuted int eigrp with a tag of 1000, then eigrp is being redistibuted back into bgp except for the tagged routes. 10.33.254.20 is actually our backup dmvpm router which is where the eigrp route is coming from, I just can't figure out why the bgp route isnt being put into the routing table instead of the eigrp route. Note it is working correctly on about 50 sites and just about 10 are doing this. Also if you look at an eigrp neigh, this route doesnt have the 1000 tag. Perhaps, I am redistributing the route and learning the routes via dmvpn, and the dmvpn router has a better cost than the redistributed route, but bgp route should still be installed due to admin distance right?
router2#sho ip bgp 10.35.10.0
BGP routing table entry for 10.35.10.0/24, version 170673
Paths: (2 available, best #2, table Default-IP-Routing-Table)
Advertised to update-groups:
1 2
65000 10
147.225.157.153 from 147.225.157.153 (159.24.198.5)
Origin IGP, localpref 100, valid, external
Local
10.33.254.20 from 0.0.0.0 (10.40.33.4)
Origin incomplete, metric 25858816, localpref 100, weight 32768, valid, sourced, best
router2#sho ip route 10.35.10.0
Routing entry for 10.35.10.0/24
Known via "eigrp 136", distance 90, metric 25858816, type internal
Redistributing via eigrp 136, bgp 1
Advertised by bgp 1 route-map eigrp_to_bgp
Last update from 10.33.254.20 on FastEthernet0/0, 6d00h ago
Routing Descriptor Blocks:
* 10.33.254.20, from 10.33.254.20, 6d00h ago, via FastEthernet0/0
Route metric is 25858816, traffic share count is 1
Total delay is 10110 microseconds, minimum bandwidth is 100 Kbit
Reliability 255/255, minimum MTU 1400 bytes
Loading 198/255, Hops 2
Solved! Go to Solution.
12-07-2010 04:15 PM
so the route is in bgp and eigrp yet eigrp is in ip routing table
RC002VPN2#sho ip eigrp top 10.35.9.0/24
IP-EIGRP (AS 136): Topology entry for 10.35.9.0/24
State is Passive, Query origin flag is 1, 1 Successor(s), FD is 25861120
Routing Descriptor Blocks:
10.33.254.20 (FastEthernet0/0), from 10.33.254.20, Send flag is 0x0
Composite metric is (25861120/25858560), Route is Internal
Vector metric:
Minimum bandwidth is 100 Kbit
Total delay is 10200 microseconds
Reliability is 255/255
Load is 56/255
Minimum MTU is 1400
Hop count is 2
RC002VPN2#sho ip bgp 10.35.9.0/24
BGP routing table entry for 10.35.9.0/24, version 170832
Paths: (2 available, best #2, table Default-IP-Routing-Table)
Advertised to update-groups:
1 2
65000 9
147.225.157.153 from 147.225.157.153 (159.24.198.5)
Origin IGP, localpref 100, valid, external
Local
10.33.254.20 from 0.0.0.0 (10.40.33.4)
Origin incomplete, metric 25861120, localpref 100, weight 32768, valid, sourced, best
RC002VPN2#sho ip route 10.35.9.0/24
^
% Invalid input detected at '^' marker.
RC002VPN2#sho ip route 10.35.9.0
Routing entry for 10.35.9.0/24
Known via "eigrp 136", distance 90, metric 25861120, type internal
Redistributing via eigrp 136, bgp 1
Advertised by bgp 1 route-map eigrp_to_bgp
Last update from 10.33.254.20 on FastEthernet0/0, 6d09h ago
Routing Descriptor Blocks:
* 10.33.254.20, from 10.33.254.20, 6d09h ago, via FastEthernet0/0
Route metric is 25861120, traffic share count is 1
Total delay is 10200 microseconds, minimum bandwidth is 100 Kbit
Reliability 255/255, minimum MTU 1400 bytes
Loading 56/255, Hops 2
12-08-2010 04:04 AM
So I see
BGP routing table entry for 10.35.9.0/24, version 170832
Paths: (2 available, best #2, table Default-IP-Routing-Table)
Advertised to update-groups:
1 2
65000 9
147.225.157.153 from 147.225.157.153 (159.24.198.5)
Origin IGP, localpref 100, valid, external
Local
10.33.254.20 from 0.0.0.0 (10.40.33.4)
Origin incomplete, metric 25861120, localpref 100, weight 32768, valid, sourced, best
IMHO, you need to configure something like:
router bgp 1
redistribute eigrp 136 route-map eigrp-to-bgp
route-map eigrp-to-bgp deny 10
match tag 1000
route-map eigrp-to-bgp permit 20
set local-preference 50
set weight 0
HTH,
Milan
12-08-2010 05:59 AM
that may fix it but it doesnt answer the core question here, why is the eigrp route in the routing table instead of the bgp route. If the bgp route was in the routing table, this would all be moot as there would be no eigrp route to redistirbute, and since the bgp route has an admin distance of 20 vs 90 for eigrp, I'm kind of confused.
12-08-2010 06:28 AM
Because from BGP process point of view the best route is that one which had been redistributed from EIGRP.
As it was only redistributed, it can't be handled like a BGP route, it's still an EIGRP route from the RIB point of view.
If you try my fix, you'll see the route coming from eBGP will become the best one from the BGP process point of view and will also be installed into the RIB as a BGP route.
BR,
Milan
12-08-2010 11:08 AM
ok, I think I am going to set the weight on all of my bgp routes to > 32768, thanks for your help.
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