In addition to sites suggested by others I can recommend:

https://ifconfig.co/

and since we are on TBB, naturally TBB's tool:

https://www.thinkbroadband.com/tools/what-is-my-ip

for the test-ipv6 site there is a GB mirror here:

https://test-ipv6.noroutetohost.net/

Edited by prlzx (Wed 15-May-24 19:08:23)

Thanks for all the comments.
To answer in order:
https://iplocation.io/ gave the expected response a few weeks ago.
The other tools suggested also say that I don't have IPv6.
I do know that I asked Zen for IPv6. That's why I said it is 'enabled on my account.' It was nearly a year ago, as it happens, and I have the email with the details to hand.
Can't help wondering if it has anything to do with a router firmware upgrade the other day. I'll try disabling IPv6 and reenabling it and see if that makes any difference. If it doesn't I'll see what Zen say.
Thanks again.

Note that these tools check by making connections from your local computing (user) device to the website rather than from the router itself.

So for anything concerning IPv6 what matters is whether your user device has a global address, and that is easy enough to spot as it starts with a 2xxx or 3xxx.

In turn that means an update to the user device (be it an OS update, or some security software) or browser settings or ad/script blocker is just a likely to be a reason.

So in this situation compare on user devices that can display their own address without needing to consult a website in conjunction with the how the router is issuing them. Usually found under Network Status or words to that effect.

* SLAAC for stateless autoconfiguration where the router only issues a prefix (first half) and the user device picks its own interface address (second half) to complete it
* DHCPv6 where the router issues a prefix but also defines a pool of host addresses and assigns them individually.

If you check DNS resolution of something like www.example.net
with commands such as host, dig, drill, nslookup, or as appropriate to your OS

and you can ping it on both the IPv4 and IPv6 address (starts with 2606:2800:21f:cb07:…) then the basic networking is probably ok.

Edited by prlzx (Thu 16-May-24 04:00:19)

If you had IPv6 working in the past and it is not now then it is quite possible that you have been migrated to Zens backhaul .

After I was migrated ~2 years ago my IPv6 stopped working (router logs showed it was no longer getting a response from a DHCPv6 server)..
A quick email to ipv6@zen,co.uk and it was fixed - despite offering IPv6 for many years it appears that their systems are still not properly integrated so the migration did not automatically trigger a reconfiguration for the IPv6 part.

I emailed Zen's IPv6 division and they disabled my original IPv6 and applied a new IPv6 address to my account, but I still wasn't getting IPv6 results from the various IP address websites. I reported this to Zen who confirmed that I was IPv6 enabled and told me to Google 'what is my IP address' which I did, getting a positive result from https://whatismyipaddress.com/ and the other sites that I had tried before. Whether this was coincidence or whether Zen had unwittingly nudged something, I have no idea, but I'm satisfied with the outcome.

the only problem i've had with IPv6 with Zen is that no matter what router or firewall changes I make it will never let ICMPv6 pings through

Interesting. I ping one of my Raspberry Pis every 5 minutes from outside using IPv6 on Zen and it works perfectly, so you (or Zen) must have a misconfiguration somewhere.

I use OpnSense as a router/firewall. IPv6 configuration isn't trivial but it works fine once configured correctly.

Im guessing since it persists even with a non-zen supplied router and I have confirmed that my firewall is allowing ICMPv6 pings through that there is likely an issue on their end. I'll give them a message and see if they can help