[c-nsp] Level3/Cogent/HVDataNet specific routing problem - looking for suggestions

[Tim Durack]

Having difficulties with routing through a Level3 circuit:

Traceroute using 67.99.58.158 source address:

RTR-3#traceroute 38.102.194.142

Type escape sequence to abort.
Tracing the route to HudsonValleyDataNet.demarc.cogentco.com (38.102.194.142)

  1 67.99.58.157 [AS 6395] 8 msec 4 msec 4 msec
  2 so-7-0-0.edge5.NewYork1.Level3.net (4.68.63.17) [AS 6395] 12 msec
4 msec 4 msec
  3 ae-32-89.car2.NewYork1.Level3.net (4.68.16.132) [AS 6395] 4 msec 4
msec 4 msec
  4 COGENT-COMM.car2.NewYork1.Level3.net (4.68.111.46) [AS 6395] 8
msec 4 msec 4 msec
  5 v3503.na21.b001105-25.jfk05.atlas.cogentco.com (38.20.32.162) [AS
6395] 12 msec 12 msec 8 msec
  6 HudsonValleyDataNet.demarc.cogentco.com (38.102.194.142) [AS 6395]
152 msec *  8 msec


Traceroute using 208.74.141.252 source address:

RTR-3#traceroute
Protocol [ip]:
Target IP address: 38.102.194.142
Source address: 208.74.141.252
Numeric display [n]:
Timeout in seconds [3]:
Probe count [3]:
Minimum Time to Live [1]:
Maximum Time to Live [30]:
Port Number [33434]:
Loose, Strict, Record, Timestamp, Verbose[none]:
Type escape sequence to abort.
Tracing the route to HudsonValleyDataNet.demarc.cogentco.com (38.102.194.142)

  1 67.99.58.157 [AS 6395] 4 msec 4 msec 4 msec
  2 so-7-0-0.edge5.NewYork1.Level3.net (4.68.63.17) [AS 6395] 4 msec 4
msec 4 msec
  3 ae-32-89.car2.NewYork1.Level3.net (4.68.16.132) [AS 6395] 4 msec
    ae-22-79.car2.NewYork1.Level3.net (4.68.16.68) [AS 6395] 4 msec 4 msec
  4 COGENT-COMM.car2.NewYork1.Level3.net (4.68.111.46) [AS 6395] 20 msec 4 msec
  5  *  *  *
  6  *  *  *
  7

I'm assuming 208.74.141.0/24 is getting dropped at hop 5 due to
filtering. Not having issues anywhere else.

I have a ticket open with Level3, but would like to see if I can work
around this with some community triggered prepending.

Looking at Level3's community support, I think I could get
208.74.141.0/24 prepended for Cogent peering:

--------------------------------------------------------
customer traffic engineering communities - Prepending
--------------------------------------------------------
65001:0   - prepend once  to all peers
65001:XXX - prepend once  at peerings to AS XXX
65002:0   - prepend twice to all peers
65002:XXX - prepend twice at peerings to AS XXX
65003:0   - prepend 3x to all peers
65003:XXX - prepend 3x    at peerings to AS XXX
65004:0   - prepend 4x to all peers
65004:XXX - prepend 4x    at peerings to AS XXX


So something like:

route-map level3-out
 set community 65001:174
!

Does that have a chance of working? Do I have to soft-reset the
session to get the community propagated?

Thanks,

Tim:>