Comcast6.net PMTU broken
ryan at u13.net
Tue Apr 17 23:24:35 CEST 2012
From a host behind a 6in4 tunnel a request to www.comcast6.net hangs. It looks like a PMTU brokenness issue since the connection is established and the request is sent successfully.
Requesting the same page from a host with a 1500B path MTU succeeds.
nova-dhcp-host111:tmp ryan$ wget http://www.comcast6.net
--2012-04-17 17:17:16-- http://www.comcast6.net/
Resolving www.comcast6.net (www.comcast6.net)... 2001:558:1002:4:68:87:29:36, 126.96.36.199
Connecting to www.comcast6.net (www.comcast6.net)|2001:558:1002:4:68:87:29:36|:80... connected.
HTTP request sent, awaiting response... ^C
This only happens with 2001:558:1002:4:68:87:29:36. 2001:558:1004:9:69:242:76:78 (which I've seen listed for www.comcast6.net though I do not see it in DNS currently) does not have this problem
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