I just tried to visit
Laser charged glowing display - Hack a Day but the page
kept loading forever. The problem is with loading page content (images and
scripts) from
s0.wp.com,
s1.wp.com,
s2.wp.com.
All of which seem to be part of wordpress hosting and come via the edgecast
content distribution network:
koos@machiavelli:~$ host s0.wp.com
s0.wp.com is an alias for cs82.wac.edgecastcdn.net.
cs82.wac.edgecastcdn.net has address 93.184.220.111
cs82.wac.edgecastcdn.net has IPv6 address 2606:2800:234:1922:15a7:17bf:bb7:f09
koos@machiavelli:~$ host s1.wp.com
s1.wp.com is an alias for cs82.wac.edgecastcdn.net.
cs82.wac.edgecastcdn.net has address 93.184.220.111
cs82.wac.edgecastcdn.net has IPv6 address 2606:2800:234:1922:15a7:17bf:bb7:f09
koos@machiavelli:~$ host s2.wp.com
s2.wp.com is an alias for cs82.wac.edgecastcdn.net.
cs82.wac.edgecastcdn.net has address 93.184.220.111
cs82.wac.edgecastcdn.net has IPv6 address 2606:2800:234:1922:15a7:17bf:bb7:f09
And all suffer from a reachability problem via IPv6:
koos@machiavelli:~$ telnet s0.wp.com 80
Trying 2606:2800:234:1922:15a7:17bf:bb7:f09...
Taking a while to fall back to IPv4, which results in long page loading
times. I noticed this on other sites too, like pages using gravatar. Which
uses the same cdn with the same problem:
koos@machiavelli:~$ host 0.gravatar.com
0.gravatar.com is an alias for cs91.wac.edgecastcdn.net.
cs91.wac.edgecastcdn.net has address 68.232.35.121
cs91.wac.edgecastcdn.net has IPv6 address 2606:2800:234:124e:17ca:871:eb2:2067
koos@machiavelli:~$ telnet 0.gravatar.com 80
Trying 2606:2800:234:124e:17ca:871:eb2:2067...
Seems edgecast has an IPv6 reachability problem from here (home, xs4all IPv6)
but not from other places. I can't reach the edgecast site either since it's
on their own network. Or at least I can't via the squid proxy, I can when
not using a proxy, since firefox has its own ideas about timeouts.
I tried to notify edgecast via e-mail and twitter.
Update 2012-11-12:
Noted by others:
WordPress IPv6 Issues - dereenigne.org seeing something more like PMTU
problems.
And Edgecast is working on it:
Thanks, @jmccrohan and @khoos. We're working hard on this right now. More soon. cc @florianoverkamp @cwoodfield
After a few changes and a lot of testing, we believe the IPv6 issue experienced by some users is now resolved.
But I'm still seeing routing issues:
$ traceroute6 www.edgecast.com
traceroute to www.edgecast.com (2606:2800:234:1df9:13d:1d4e:6b0:10cf) from 2001:980:14ca:61::13, port 33434, from port 44865, 30 hops max, 60 byte packets
1 lo1.dr4.1d12.xs4all.net (2001:888:0:4401::1) 15.529 ms 14.870 ms 16.175 ms
2 1314.ae3.xr3.3d12.xs4all.net (2001:888:0:4403::2) 15.349 ms 16.757 ms 14.426 ms
3 0.ge-1-2-0.xr1.sara.xs4all.net (2001:888:1:4005::1) 17.594 ms 16.123 ms 15.212 ms
4 ge-0.ams-ix.amstnl02.nl.bb.gin.ntt.net (2001:7f8:1::a500:2914:1) 17.108 ms 16.405 ms 15.552 ms
5 ae-2.r03.amstnl02.nl.bb.gin.ntt.net (2001:728:0:2000::12a) 18.093 ms 17.441 ms 16.083 ms
6 * * *
7 * * *
8 * * *
9 * * *
Update 2012-11-15:
More traceroutes to test. It seems the only thing unreachable is exactly the
/48 which holds the IPv6 content server(s).
Update 2012-12-07:
A network engineer at xs4all contacted Edgecast and got the problem solved
pronto. I guess he has a better entry point!
koos@greenblatt:~$ telnet -6 www.edgecast.com 80
Trying 2606:2800:234:1df9:13d:1d4e:6b0:10cf...
Connected to www.edgecast.com.
Escape character is '^]'.