Thanks to all who replied! The customer reduced their prepends, and now we're advertising the route upstream.
I appreciate the help. Thanks, Adam -----Original Message----- From: Scott Granados [mailto:[email protected]] Sent: Monday, July 29, 2013 10:43 PM To: Adam Greene Cc: [email protected] Subject: Re: [c-nsp] BGP re-announcement question This is correct, in your set up, the customer learned route is not the best route. If you want to preserve the prepends I would increase the pref of your learned customers so you install them as the most preferred. Thanks Scott On Jul 29, 2013, at 6:53 PM, Adam Greene <[email protected]> wrote: > Hi! > > > > We are receiving a heavily prepended route announcement from a > customer and are trying to re-announce it to our upstream provider, without success. > > > > We learn the route on router A via eBGP. Router A announces the route > to Router B via iBGP. Router B is then supposed to announce it to > Router C, our upstream provider, via eBGP, but it is not. > > > > Here is what Router B is seeing: > > > > 7206VXR#sh ip bgp 198.11.15.0 > > BGP routing table entry for 198.11.15.0/24, version 262804866 > > Paths: (2 available, best #2, table Default-IP-Routing-Table) > > > > 27241 27241 27241 27241 27241 27241, (received & used) > > 204.8.83.14 (metric 1) from 172.18.18.20 (172.18.18.20) > > Origin IGP, metric 300, localpref 100, valid, internal > > 12271 7843 3356 46887 27241, (received & used) > > 24.29.112.25 from 24.29.112.25 (69.193.224.79) > > Origin IGP, localpref 100, valid, external, best > > Community: 7843:2161 7843:2303 7843:2313 > > > > As you can see, the eBGP route Router B is receiving from Router C > (upstream) is considered the best route. Is that why we are not > reannouncing it back upstream? > > > > Prefix-lists and route-maps have all been checked, including regular > expressions; we allow out ^27241(_27241)*$ and a "sh ip bgp regexp > ^27241(_27241)*$" provides this output: > > > > Network Next Hop Metric LocPrf Weight Path > > * i198.11.15.0 204.8.83.14 300 100 0 27241 27241 > 27241 27241 27241 27241 i > > > > I do wonder a bit about the "metric 300" (I think my customer might be > trying to weight things) but I'm not sure that's coming into play here > or not. > > > > This was working fine recently, with no changes on our end, but the > customer was announcing without any prepends, and I'm not sure if the origin was "?" > before, or "i" like it is now. > > > > Thanks, > > Adam > > _______________________________________________ > cisco-nsp mailing list [email protected] > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
