[c-nsp] BGP Med and outbound metric

[Matthew Huff]

Since we use BGP as peering to our ISPs, and don't use BGP internally in our core, I haven't used MED or local_pref much. However, we have two routers connected to another ASN (not via the internet) and I'm trying to influence their return path since we are getting asynchronous routing. I'm trying to use MED to advertise a lower preference out our second router but it doesn't seem to be working. Any suggestions?

Here is the config...

router bgp 14607
 ...
neighbor 10.151.0.82 remote-as 26585
neighbor 10.151.0.82 distribute-list bgp_distribute_cap in
neighbor 10.151.0.82 distribute-list bgp_distribute_core_plus_ecn out
neighbor 10.151.0.82 route-map setMED-LOW out
neighbor 10.151.0.82 filter-list 10 out

route-map setMED-LOW permit 10
 match ip address routemap_ecn
 set metric 200

ip access-list standard routemap_ecn
 permit 129.77.44.0

I've done the "clear ip bgp * soft" and have verified that the other side has seen the change (previously I had a block all access list on the distribute out so I know that the change has taken effect).

rtr-feed2#show ip bgp 129.77.44.0
BGP routing table entry for 129.77.44.0/24, version 22
Paths: (1 available, best #1, table default)
  Advertised to update-groups:
     3         
  Local
    0.0.0.0 from 0.0.0.0 (129.77.40.42)
      Origin incomplete, metric 0, localpref 100, weight 32768, valid, sourced, best

rtr-feed2#show ip bgp neighbors 10.151.0.82 advertised-routes 
BGP table version is 198, local router ID is 129.77.40.42
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path
*> 129.77.44.0/24   0.0.0.0                  0         32768 ?

Total number of prefixes 1


Both outputs show a metric of 0. Any ideas?

----
Matthew Huff       | One Manhattanville Rd
OTA Management LLC | Purchase, NY 10577
http://www.ox.com  | Phone: 914-460-4039
aim: matthewbhuff  | Fax:   914-460-4139