[funwithjustin]

Serious question - what could cause this? I don't know much about network configuration or DNS. Could it be a coordinated attack on Comcast's infrastructure somewhere? Seems a little crazy that they'd be experiencing problem nation-wide with no redundancy baked into their system.

I tried manually flipping over to Google's DNS servers with the same result.

[Shelnutt2]

Since we are resolving dns, we know its not a dns issue. This appears to be pack loss / routing issue. The most likely cause of this is someone has leaked internal routes, or leaked bgp.

I don't see anything from bgpmon (https://twitter.com/bgpmon) or bgpstream (https://twitter.com/bgpstream) for North America though. There have been multiple bgp leaks today but nothing that I can see that effects comcast/rnc.

It does appear at least some site I'm seeing are being routed through Europe.

  traceroute kayak.com
  traceroute to kayak.com (185.6.169.69), 64 hops max, 52 byte packets
   2  96.120.68.17 (96.120.68.17)  7.840 ms  8.995 ms  8.354 ms
   3  96.108.154.229 (96.108.154.229)  8.136 ms  9.174 ms  8.325 ms
   4  be-23-sur03.westroxbury.ma.boston.comcast.net (69.139.221.226)  9.879 ms  7.478 ms  7.667 ms
   5  be-20-ar01.needham.ma.boston.comcast.net (68.85.106.21)  9.527 ms  12.000 ms  8.524 ms
   6  * * *
   7  ae-1-16.bar1.zurich1.level3.net (4.69.142.129)  118.578 ms  118.947 ms  118.229 ms
   8  ae-1-16.bar1.zurich1.level3.net (4.69.142.129)  127.931 ms  116.424 ms  117.852 ms
   9  nexellent-a.bar1.zurich1.level3.net (213.242.82.110)  118.340 ms  117.555 ms  115.950 ms

[Eyght]

Seems like the UK and Germany are under relatively heavy load right now.

https://www.akamai.com/uk/en/solutions/intelligent-platform/...

[funwithjustin]

Thanks for the info. How on earth could Comcast have a single point of failure for their entire network nation-wide?

Would this suggest that there's possibly something like a MITM attack going on that's hijacking their traffic somewhere?

[tclancy]

>Thanks for the info. How on earth could Comcast have a single point of failure for their entire network nation-wide?

I guess I've been a Comcast customer too long given I don't even understand your question. It would seem more shocking if it were not something like this.

[quwert95]

I'm in the SF Bay Area and after looking at traceroutes and packet loss it looks like something at PAIX has failed between Comcast, Hurricane Electric, NTT, and others.

A coordinated attack could be a cause of something like this, but more often than not it's a hardware or power failure at a critical exchange like PAO, DFW, IAD, etc. Also possible, human error in turning down traffic to certain servers, networks, and IP ranges.

[_rpd]

> what could cause this?

It could be ...

The Backhoe, The Internet's Natural Enemy (2006)

https://it.slashdot.org/story/06/01/19/1643215/the-backhoe-t...