topic O2 website broken for ipv6 in Tech Support

O2 website broken for ipv6

AndyQ — Thu, 30 Oct 2025 22:35:45 GMT

The https://www.o2.co.uk website is not responding to IPv6 requests, despite having an AAAA record in DNS. Is there any way I can notify them, and will they care?

https://drive.google.com/file/d/1AZ8wCeuvYOt14v1A8JDHbLMX1JNz3Oee/view?usp=drive_link

Re: O2 website broken for ipv6

MI5 — Thu, 30 Oct 2025 23:15:13 GMT

@AndyQ wrote:
Is there any way I can notify them, and will they care?

@AndyQ

Message them on Social Media. Facebook or Instagram https://www.o2.co.uk/abouto2/social-media but probably won't do anything about it.

Re: O2 website broken for ipv6

madasaf1sh — Fri, 31 Oct 2025 08:45:36 GMT

@AndyQ

I will tell you now that IPv6 requests to the website will be so far down the Network teams list of priorities.

And where are you seeing the AAAA record as there are none published in DNS, and Im clicking a rando, link on a forum, to someones Google Drive..

This is from checking Cloudflare, OpenDNS, Authoritative, and many more..

Re: O2 website broken for ipv6

AndyQ — Fri, 31 Oct 2025 10:04:09 GMT

There are some CNAMEs that lead somewhere

andy@Gertrude:~$ curl --verbose -6 www.o2.co.uk
* Trying 2620:1ec:bdf::64:80...
* Immediate connect fail for 2620:1ec:bdf::64: Network is unreachable
* Trying 2620:1ec:46::64:80...
* Immediate connect fail for 2620:1ec:46::64: Network is unreachable
* Closing connection 0
curl: (7) Couldn't connect to server

Re: O2 website broken for ipv6

madasaf1sh — Fri, 31 Oct 2025 10:26:38 GMT

@AndyQ

Thats odd as o2.co.uk doesnt present any cnames on IPv4 or IPv6 when querying o2 Name Servers n2.o2.net and n3.o2.net

It looks like a misconfiguration as that IPv6 address belongs to Azure, what DNS server are you using to connect.

Re: O2 website broken for ipv6

AndyQ — Fri, 31 Oct 2025 12:18:26 GMT

A dig for the naked domain doesn't give any AAAA records (and zone origins aren't supposed to have CNAMEs). But a dig for www.o2.co.uk at 1.1.1.1 (etc) gives

andy@Gertrude:~$ dig AAAA www.o2.co.uk @1.1.1.1

; <<>> DiG 9.18.39-0ubuntu0.22.04.2-Ubuntu <<>> AAAA www.o2.co.uk @1.1.1.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 36127
;; flags: qr rd ra; QUERY: 1, ANSWER: 6, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
;; QUESTION SECTION:
;www.o2.co.uk. IN AAAA

;; ANSWER SECTION:
www.o2.co.uk. 247 IN CNAME feproxy-www.azurefd.net.
feproxy-www.azurefd.net. 60 IN CNAME mr-azurefd.tm-azurefd.net.
mr-azurefd.tm-azurefd.net. 60 IN CNAME shed.dual-low.part-0036.t-0009.t-msedge.net.
shed.dual-low.part-0036.t-0009.t-msedge.net. 60 IN CNAME part-0036.t-0009.t-msedge.net.
part-0036.t-0009.t-msedge.net. 60 IN AAAA 2620:1ec:bdf::64
part-0036.t-0009.t-msedge.net. 60 IN AAAA 2620:1ec:46::64

and a dig at n2.02.net give the CNAME (but doesn't have caches of the other data)

andy@Gertrude:~$ dig AAAA www.o2.co.uk @N2.02.net

; <<>> DiG 9.18.39-0ubuntu0.22.04.2-Ubuntu <<>> AAAA www.o2.co.uk @N2.02.net
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 43821
;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 13, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;www.o2.co.uk. IN AAAA

;; ANSWER SECTION:
www.o2.co.uk. 900 IN CNAME feproxy-www.azurefd.net.

I think you're right that they won't see it as high priority. And I don't have any social media accounts to be able to tell them anyway! So I guess I need to hotspot from mobile data (v4 only) when I need anything.

Thanks all