BGP.guru

BGP.guru

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04 May 2014

Leaking Routes

The traceroute:

$ tcptraceroute -q1 ciscodude.net
Selected device eth0, address 10.xx.xx.5, port 36975 for outgoing packets
Tracing the path to ciscodude.net (206.220.195.237) on TCP port 80 (http), 30 hops max
 1  10.xx.xx.254  0.399 ms
 2  198.62.164.2  0.456 ms
 3  ra2nr-ge3-2-20.wp.bigpipeinc.com (66.244.208.1)  1.254 ms
 4  rc3sc-tge0-1-0-34.wp.shawcable.net (66.163.73.165)  1.694 ms
 5  rc2nr-hge0-19-0-0.wp.shawcable.net (66.163.73.197)  1.663 ms
 6  66.163.76.22  24.716 ms
 7  ra1fs-tge1-3.mt.shawcable.net (66.163.66.34)  22.460 ms
 8  rx0sh-terago.mt.bigpipeinc.com (66.244.223.206)  23.163 ms
 9  bvi1.asr01.tor151f.fibrenoire.ca (206.108.34.141)  22.915 ms
10  te0-2.mdr01.tor151f.fibrenoire.ca (68.67.63.185)  22.504 ms
11  131.gi0-1.cr1.360ptg.winnipeg.as14866.net (173.231.121.50)  46.706 ms
12  vl77.ar1.400wb.ywg.as14866.net (206.220.192.2)  46.430 ms
13  vl66.sw1.400wb.ywg.voinetworks.ca (206.220.199.217)  48.233 ms
14  vl59.sw1.134sm.ywg.voinetworks.ca (206.220.199.49)  66.890 ms
15  vl240.sw1.henchman21.net (206.220.199.131)  56.119 ms
16  vl198-l3-theo.ciscodude.net (206.220.198.171)  71.401 ms
17  ciscodude.net (206.220.195.237) [open]  77.420 ms

The hop in question is hop 8. TeraGo? That’s strange, they used to be an AS14866 transit provider, I wonder if this is related. I confirmed that my route received at AS62758 had TeraGo in the AS-PATH (6327 20161 22652 14866), and contacted Fibrenoire. Since traceroutes to other IP ranges advertised by AS14866 did not go through TeraGo, I immediately suspected an old prefix-list had been merged into TeraGo’s configuration.

A traceroute to another subnet:

$ tcptraceroute -q1 192.69.40.1
Selected device eth0, address 10.xx.xx.5, port 60031 for outgoing packets
Tracing the path to 192.69.40.1 on TCP port 80 (http), 30 hops max
 1  10.xx.xx.254  0.376 ms
 2  198.62.164.2  0.424 ms
 3  ra2nr-ge3-2-20.wp.bigpipeinc.com (66.244.208.1)  1.056 ms
 4  66.163.73.161  1.863 ms
 5  66.163.75.117  17.385 ms
 6  10gigabitethernet4-1.core1.chi1.he.NET (206.223.119.37)  17.233 ms
 7  100ge13-1.core1.msp1.he.net (184.105.223.178)  25.297 ms
 8  10ge1-3.core1.ywg1.he.net (184.105.80.14)  33.167 ms
 9  voi-networks-inc.gigabitethernet2-23.core1.ywg1.he.net (216.66.78.250)  33.346 ms
10  vl77.ar1.400wb.ywg.as14866.net (206.220.192.2)  39.940 ms
11  1-0.premium-gige.winnipeg.voinetworks.net (192.69.40.1) [closed]  41.241 ms

Completely different path (6327 6939 14866). Shaw’s nearest peering point with Hurricane is in Chicago. TeraGo is a Shaw transit customer. Hence, Shaw would localpref routes received via their customer, TeraGo, higher, and prefer the longer path.

The reverse path (from AS14866 to AS62758):

$ traceroute -q1 198.62.164.30
traceroute to 198.62.164.30 (198.62.164.30), 64 hops max, 52 byte packets
traceroute to 198.62.164.30 (198.62.164.30), 64 hops max, 52 byte packets
 1  vl202-l3-theo (192.168.202.254)  4.338 ms
 2  vl218.sw1.henchman21.net (206.220.198.165)  2.763 ms
 3  vl240.sw1.134sm.ywg.voinetworks.ca (206.220.199.130)  7.811 ms
 4  vl59.sw1.400wb.ywg.voinetworks.ca (206.220.199.50)  19.485 ms
 5  vl66.ar1.400wb.ywg.as14866.net (206.220.199.218)  7.189 ms
 6  80.po-channel1.cr2.167lom.ywg.as14866.net (206.220.199.5)  12.016 ms
 7  ge2-23.core1.ywg1.he.net (216.66.78.249)  33.133 ms
 8  10ge1-6.core1.msp1.he.net (184.105.80.13)  92.778 ms
 9  100ge7-1.core1.chi1.he.net (184.105.223.177)  55.346 ms
10  *
11  66.163.75.118 (66.163.75.118)  55.439 ms
12  ra2nr-tge1-1.wp.shawcable.net (66.163.73.166)  69.597 ms
13  h72-2-15-250.bigpipeinc.com (72.2.15.250)  78.848 ms
14  198.62.164.30 (198.62.164.30)  63.208 ms

This issue has not yet been resolved by TeraGO NOC yet, this post will be updated as the situation unfolds.

Update

Issue was not resolved by TeraGO, and instead TeraGO was depeered by FibreNoire.


Theodore Baschak - Theo is a network engineer with experience operating core internet technologies like HTTP, HTTPS and DNS. He has extensive experience running service provider networks with OSPF, MPLS, and BGP.