www.java.com

[#1]

Hurricane Electric's IPv6 DNS is 2001:470:20::2

[#2]

I've added 2001:4860:4860::8888 to the router with metric 0.

[#3]

v6 Lookups for www.java.com:
PN (212.159.13.49 and 212.159.13.49)

Quote

www.java.com. 652 IN CNAME www.java.com.edgekey.net. www.java.com.edgekey.net. 15497 IN CNAME e7075.dscx.akamaiedge.net. e7075.dscx.akamaiedge.net. 20 IN AAAA 2a02:26f0:5a:281::1ba3 e7075.dscx.akamaiedge.net. 20 IN AAAA 2a02:26f0:5a:282::1ba3

OpenDNS (2620:0:ccc::2 and 2620:0:cccd::2)

Quote

;; ANSWER SECTION: www.java.com. 830 IN CNAME www.java.com.edgekey.net. www.java.com.edgekey.net. 6066 IN CNAME e7075.dscx.akamaiedge.net. e7075.dscx.akamaiedge.net. 20 IN AAAA 2a02:26f0:5a:281::1ba3 e7075.dscx.akamaiedge.net. 20 IN AAAA 2a02:26f0:5a:282::1ba3

Google (2001:4860:4860::8888 and 2001:4860:4860::8844)

Quote

;; ANSWER SECTION: www.java.com. 417 IN CNAME www.java.com.edgekey.net. www.java.com.edgekey.net. 3976 IN CNAME e7075.dscx.akamaiedge.net. e7075.dscx.akamaiedge.net. 19 IN AAAA 2a02:26f0:97:29e::1ba3 e7075.dscx.akamaiedge.net. 19 IN AAAA 2a02:26f0:97:2a2::1ba3

Hurricane Electric (2001:470:20::2)

Quote

;; ANSWER SECTION: www.java.com. 521 IN CNAME www.java.com.edgekey.net. www.java.com.edgekey.net. 4179 IN CNAME e7075.dscx.akamaiedge.net. e7075.dscx.akamaiedge.net. 20 IN AAAA 2a02:26f0:5d:289::1ba3 e7075.dscx.akamaiedge.net. 20 IN AAAA 2a02:26f0:5d:2a5::1ba3

If PN's DNS servers use Hurricane's DNS for v6, why do they give different lookups?

[#4]

Java's website is served by Akamai's content delivery network hence as part of the load balancing different DNS servers will be provided with different IP addresses for the content based on their geographic/network location. In particular, all the records are aliases of different points on Akamai's network and hence all ultimately resolve to Akamai-owned IP addresses.

Quote from: AndyH

If PN's DNS servers use Hurricane's DNS for v6, why do they give different lookups?

PN's DNS servers are HE's DNS servers however they are anycasted hence whilst there may be a single address they are represented by multiple servers. Each one may receive a different result based on their location given the above.

[#5]

Thanks for the explanation - that makes perfect sense.
It's still a bit strange that I cannot access www.java.com over any v6 address though. Another mystery!

[#6]

Quote from: purleigh

I'm having no trouble accessing http://www.java.com using IPv6 (Hurricane Electric tunnel). Although interestingly if I use http://java.com my browser defaults to IPv4, but http://www.java.com uses IPv6. My Firefox "4or6" add-on shows the following addresses for http://www.java.com  (see attached screenshot below).

in firefox its loading on ipv4, the ipv6 is in the dns result but for whatever reason firefox is using ipv4 for the site.

[#7]

It'll be the result of Firefox's 'Happy Eyeballs' feature which, when faced with an option of connecting over IPv4 or IPv6, measures the responsiveness for a given site for each and selects the quickest. It was primarily introduced to accommodate the situation whereby a device thought it had IPv6 connectivity but in reality it didn't and yet it'd take quite some time for this fact to be realised before falling back to IPv4.

[#8]

Try adding the Firefox add-on "4or6".
In the 'Advanced' settings, try unticking the "Fast fallback to IPv4", and see whether IPv6 becomes preferred by default.
"Fast fallback" is the same as "Happy Eyeballs" described above.

[#9]

Even if I put in the v6 addresses manually, they still won't load for me in any browser. Very strange.
Edit: My traceroutes don't seem to be going any further than PN's network. Last hop is 2a02:16c8:1:2::8
Can anyone on the trial access http://[2a02:26f0:5a:282::1ba3] or http://[2a02:26f0:5a:281::1ba3] ?

[#10]

That isn't going to work because of the way that website is hosted, as the webhost requires the "www.java.com" URL to be passed from your browser to identify the site you are trying to contact.
YouTube is similar, if you lookup the IPv4 address for Youtube, you get a number of IP addresses.
If you try say http://173.194.34.128/, you don't end up in youtube, but instead you get a catch all Google page.
As I said, many hosted websites need to see the URL from the browser to full resolve what you are trying to access.
Other websites that aren't hosted in that way can be accessed using the IPv6 notation, e.g. http://[2a02:68:1::4]/ = Thinkbroadband

[#11]

What you can do is put the IPv6 address in your hosts file. Then you can address it by name and it won't do the DNS lookup and so shouldn't find the IPv4 address and fall back (you might need to flush the DNS cache).

[#12]

@ purleigh - Thanks for the explanation. The strange thing is the traceroute should still work. But for me, it doesn't get past Plusnet's network. I am wondering if there could be some peering issue?
@ jelv - Did you try this for www.java.com? I tried it and still it loads in v4.

[#13]

Try reading the first post!

Quote from: jelv

Can someone check that if they are finding www.java.com is unbelievably slow over IPv6 please. Edit: Or possibly not working at all. nslookup gives both IPv4 and IPv6 addresses, but until I forced IPv4 only for that site on my wife's PC it just wasn't responding.

[#14]

I saw, I was wondering if that was still the case though.
Whatever the issue, it seems to have been fixed. The site loads in v6 fine now.
I was going to ask if your traceroutes to 2a02:26f0:5a:282::1ba3 or 2a02:26f0:5a:281::1ba3 go no further than PN's network. But now they are working ok:

Quote

# traceroute6 2a02:26f0:5a:282::1ba3 traceroute to 2a02:26f0:5a:282::1ba3 (2a02:26f0:5a:282::1ba3), 30 hops max, 16 byte packets 1  2a02:16c8:0:1::12 (2a02:16c8:0:1::12)  5.351 ms  5.381 ms  5.132 ms 2  2a02:16c8:1:2::19 (2a02:16c8:1:2::19)  4.719 ms  4.381 ms  4.379 ms 3  2a02:16c8::d (2a02:16c8::d)  4.909 ms  4.553 ms  4.354 ms 4  2a02:16c8:1:2::8 (2a02:16c8:1:2::8)  4.406 ms  4.405 ms  4.373 ms 5  lonap.he.net (2001:7f8:17::1b1b:1)  4.460 ms  4.835 ms  4.526 ms 6  10ge3-1.core1.lon2.he.net (2001:470:0:2cd::1)  11.551 ms  4.988 ms  4.414 ms 7  ge-2-1-0-zpr1.lnt.cw.net (2001:7f8:4::4f9:1)  4.845 ms  5.073 ms  6.341 ms 8  so-0-1-0-r1-IPv6.de.cw.net (2001:5000:0:1::1)  5.006 ms  4.955 ms  4.977 ms 9  akamai-gw2.lns.cw.net (2001:5000:1100:9::2)  5.706 ms  6.602 ms  5.509 ms

[#15]

C:\Users\John>tracert 2a02:26f0:5a:282::1ba3
Tracing route to 2a02:26f0:5a:282::1ba3 over a maximum of 30 hops
  1    1 ms    <1 ms    1 ms  dsldevice.lan [hidden]
  2    22 ms    26 ms    22 ms  2a02:16c8:0:1::13
  3    21 ms    20 ms    20 ms  2a02:16c8:1:2::17
  4    20 ms    21 ms    21 ms  2a02:16c8::c
  5    20 ms    20 ms    20 ms  2a02:16c8:1:2::5
  6    21 ms    21 ms    20 ms  2a02:16c8:1:2::8
  7    *        *        *    Request timed out.
  8    *        *        *    Request timed out.