Comment 54 for bug 241305

Same problem (now with archive.ubuntu.org):
curl -vg [2001:67c:1360:8c01::18]
* Rebuilt URL to: [2001:67c:1360:8c01::18]/
* Hostname was NOT found in DNS cache
* Trying 2001:67c:1360:8c01::18...
* connect to 2001:67c:1360:8c01::18 port 80 failed: Connection timed out
* Failed to connect to 2001:67c:1360:8c01::18 port 80: Connection timed out
* Closing connection 0
curl: (7) Failed to connect to 2001:67c:1360:8c01::18 port 80: Connection timed out

Here is "dig -t AAAA archive.ubuntu.com" output:

; <<>> DiG 9.9.5-3ubuntu0.8-Ubuntu <<>> -t AAAA archive.ubuntu.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 57059
;; flags: qr rd ra; QUERY: 1, ANSWER: 6, AUTHORITY: 4, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;archive.ubuntu.com. IN AAAA

;; ANSWER SECTION:
archive.ubuntu.com. 266 IN AAAA 2001:67c:1360:8c01::18
archive.ubuntu.com. 266 IN AAAA 2001:67c:1560:8001::11
archive.ubuntu.com. 266 IN AAAA 2001:67c:1562::16
archive.ubuntu.com. 266 IN AAAA 2001:67c:1562::19
archive.ubuntu.com. 266 IN AAAA 2001:67c:1360:8c01::19
archive.ubuntu.com. 266 IN AAAA 2001:67c:1360:8001::17

;; AUTHORITY SECTION:
ubuntu.com. 516 IN NS ns4.p27.dynect.net.
ubuntu.com. 516 IN NS ns2.p27.dynect.net.
ubuntu.com. 516 IN NS ns3.p27.dynect.net.
ubuntu.com. 516 IN NS ns1.p27.dynect.net.

;; Query time: 0 msec
;; SERVER: 10.1.94.8#53(10.1.94.8)
;; WHEN: Thu Apr 14 13:59:28 MSK 2016
;; MSG SIZE rcvd: 301