Re: buildfarm server suddenly not talking to old SSL stacks? - Mailing list pgsql-www

On 07/17/2018 09:22 PM, Tom Lane wrote:
> Stefan Kaltenbrunner <stefan@kaltenbrunner.cc> writes:
>> On 07/17/2018 08:58 PM, Tom Lane wrote:
>>> Now I'm completely confused.  This is going through a different ISP
>>> and significantly different network path to reach rackspace, but
>>> that shouldn't have anything to do with it?  *Something* is darn
>>> weird here.
> 
>> given it does not yet seem to have been discussed in this thread - ipv4
>> vs ipv6 (either direct or indirect through CGN or similiar technologies)?
> 
> Good thought, but at least at my end it's all IPv4, and traceroute
> doesn't suggest there's anything else between.  The RHEL6 box sees
> this traceroute:
> 
> $ traceroute buildfarm.postgresql.org
> traceroute to buildfarm.postgresql.org (174.143.35.217), 30 hops max, 60 byte packets
>  1  router1.sss.pgh.pa.us (192.168.168.5)  3.705 ms  4.465 ms  5.528 ms
>  2  192.168.252.29 (192.168.252.29)  18.278 ms  19.285 ms  20.719 ms
>  3  gw.aspStation.net (66.207.128.1)  22.197 ms  23.351 ms  24.578 ms
>  4  144.232.10.211 (144.232.10.211)  25.990 ms  27.226 ms  28.582 ms
>  5  144.232.10.210 (144.232.10.210)  29.884 ms  31.063 ms  33.532 ms
>  6  144.232.14.7 (144.232.14.7)  32.215 ms  46.337 ms  44.983 ms
>  7  144.232.15.174 (144.232.15.174)  46.679 ms 144.232.14.10 (144.232.14.10)  34.810 ms  35.586 ms
>  8  144.232.15.121 (144.232.15.121)  35.414 ms  34.871 ms  35.634 ms
>  9  sl-above1-722053-0.sprintlink.net (144.228.205.158)  35.691 ms  35.101 ms  35.580 ms
> 10  ae1.cr2.dca2.us.zip.zayo.com (64.125.20.121)  35.510 ms  34.947 ms  35.528 ms
> 11  ae27.cs2.dca2.us.eth.zayo.com (64.125.30.248)  83.111 ms  82.605 ms  87.833 ms
> 12  ae4.cs2.lga5.us.eth.zayo.com (64.125.29.30)  98.348 ms  97.706 ms  97.689 ms
> 13  ae3.cs2.ord2.us.eth.zayo.com (64.125.29.213)  85.612 ms  85.198 ms  85.710 ms
> 14  ae5.cs2.den5.us.eth.zayo.com (64.125.29.216)  85.700 ms  85.143 ms  85.800 ms
> 15  ae7.cs2.den5.us.eth.zayo.com (64.125.31.237)  91.259 ms  90.791 ms  91.310 ms
> 16  ae28.er1.dfw2.us.zip.zayo.com (64.125.26.15)  85.946 ms  69.331 ms  69.892 ms
> 17  128.177.70.86.IPYX-076520-900-ZYO.zip.zayo.com (128.177.70.86)  69.761 ms  87.568 ms  88.741 ms
> 18  * * *
> 19  74.205.108.121 (74.205.108.121)  85.957 ms be42.coreb.dfw1.rackspace.net (74.205.108.125)  85.334 ms
be41.corea.dfw1.rackspace.net(74.205.108.113)  85.820 ms
 
> 20  core5-coreb.dfw1.rackspace.net (74.205.108.27)  76.332 ms po1.CoreA.core6.dfw1.rackspace.net (72.32.111.13)
84.456ms po2.CoreB.core6.dfw1.rackspace.net (72.32.111.15)  77.344 ms
 
> 21  core5-aggr313a.dfw1.rackspace.net (67.192.56.63)  83.224 ms  82.713 ms  71.320 ms
> 22  * * *
> 23  * * *
> 24  * * *
> 25  * * *
> 26  * * *
> 27  * * *
> 28  * * *
> 29  * * *
> 30  * * *
> 
> while the buildfarm critters are going through verizon:
> 
> $ traceroute buildfarm.postgresql.org
> traceroute to buildfarm.postgresql.org (174.143.35.217), 64 hops max, 40 byte packets
>  1  router2 (192.168.168.2)  5.031 ms  4.108 ms  4.195 ms
>  2  * * *
>  3  b3309.pitbpa-lcr-22.verizon-gni.net (130.81.28.70)  133.770 ms  8.250 ms  8.069 ms
>  4  * * *
>  5  * * *
>  6  0.et-7-3-0.br1.iad8.alter.net (140.222.239.83)  16.920 ms 0.et-5-1-5.br1.iad8.alter.net (140.222.0.65)  16.547 ms
14.896 ms
 
>  7  xe-2-1-0.er2.iad10.us.zip.zayo.com (64.125.13.173)  15.706 ms  14.482 ms  14.481 ms
>  8  ae1.cr2.dca2.us.zip.zayo.com (64.125.20.121)  15.731 ms  17.841 ms  17.265 ms
>  9  ae27.cs2.dca2.us.eth.zayo.com (64.125.30.248)  68.536 ms  68.973 ms  67.971 ms
> 10  ae4.cs2.lga5.us.eth.zayo.com (64.125.29.30)  67.021 ms  68.627 ms  67.130 ms
> 11  ae3.cs2.ord2.us.eth.zayo.com (64.125.29.213)  67.277 ms  67.727 ms  68.079 ms
> 12  ae5.cs2.den5.us.eth.zayo.com (64.125.29.216)  66.520 ms  69.493 ms  73.931 ms
> 13  ae7.cs2.den5.us.eth.zayo.com (64.125.31.237)  193.146 ms  66.854 ms  67.034 ms
> 14  ae28.er1.dfw2.us.zip.zayo.com (64.125.26.15)  149.815 ms  67.910 ms  70.480 ms
> 15  128.177.70.86.ipyx-076520-900-zyo.zip.zayo.com (128.177.70.86)  68.615 ms  78.398 ms  70.127 ms
> 16  * * *
> 17  be41.coreb.dfw1.rackspace.net (74.205.108.117)  73.871 ms 74.205.108.121 (74.205.108.121)  67.374 ms  70.223 ms
> 18  core5-corea.dfw1.rackspace.net (74.205.108.11)  72.848 ms po1.corea.core6.dfw1.rackspace.net (72.32.111.13)
69.176ms core5-corea.dfw1.rackspace.net (74.205.108.11)  70.037 ms
 
> 19  po2.core6.aggr313a.rackspace.net (72.32.111.211)  203.537 ms  70.130 ms core5-aggr313a.dfw1.rackspace.net
(67.192.56.63) 70.854 ms
 
> 20  * * *
> 21  * * *
> 22  * * *
> 23  * * *
> 24  * * *
> 25  * * *
> 26  * * *
> 27  * * *
> 28  * * *
> 29  * * *
> 30  * * *
> 
> Also, if the issue is somewhere in between, that fails to explain why
> "curl" works but not perl.

not sure that proofs that v4 vs v6 is out entirely, there could be other
factors involved (like your isp mapping v4 to v6 on the router(!) maybe
combined with dns64/dns46 related tricks).
It should still be possible to figure out where exactly the "network
unreachable" comes from - whether it is something the local tcp/ip stack
generates or something that comes in as an icmp-error from remote using
tcpdump or similiar.



Stefan