Comment 51 for bug 241305

This problem appears again for me:

$ host security.ubuntu.com
security.ubuntu.com has address 91.189.91.14
security.ubuntu.com has address 91.189.91.24
security.ubuntu.com has address 91.189.92.201
security.ubuntu.com has address 91.189.91.23
security.ubuntu.com has address 91.189.91.13
security.ubuntu.com has address 91.189.92.200
security.ubuntu.com has address 91.189.91.15
security.ubuntu.com has address 91.189.88.153
security.ubuntu.com has address 91.189.88.152
security.ubuntu.com has IPv6 address 2001:67c:1560:8001::13
security.ubuntu.com has IPv6 address 2001:67c:1562::16
security.ubuntu.com has IPv6 address 2001:67c:1562::15
security.ubuntu.com has IPv6 address 2001:67c:1360:8c01::18
security.ubuntu.com has IPv6 address 2001:67c:1562::17
security.ubuntu.com has IPv6 address 2001:67c:1560:8001::11
security.ubuntu.com has IPv6 address 2001:67c:1562::14
security.ubuntu.com has IPv6 address 2001:67c:1360:8c01::19

The first IPv6 server in the list (2001:67c:1560:8001::13) does not respond at all:
$ curl -v [2001:67c:1560:8001::13]
* Rebuilt URL to: [2001:67c:1560:8001::13]/
* Trying 2001:67c:1560:8001::13...
* connect to 2001:67c:1560:8001::13 port 80 failed: No route to host
* Failed to connect to 2001:67c:1560:8001::13 port 80: No route to host
* Closing connection 0
curl: (7) Failed to connect to 2001:67c:1560:8001::13 port 80: No route to host

I tried that from two different IPv6 networks, same result.

The other IPv6 hosts return different results for /, I'm not sure if this is intended but it doesn't look good:
2001:67c:1562::16 -> Apache2 Ubuntu Default Page
2001:67c:1562::15 -> Index of /
2001:67c:1360:8c01::18 -> Index of /
2001:67c:1562::17 -> Apache2 Ubuntu Default Page
2001:67c:1560:8001::11 -> Apache2 Ubuntu Default Page
2001:67c:1562::14 -> It works!
2001:67c:1360:8c01::19 -> Index of /

All in all this issue is very annoying since IPv6 is in wide spread use now and it keeps people from installing security updates.