[_cenw]

This is great if you have IPv6 support from your ISP. Not so great if you don't.

Before someone mentions tunnels: Last time I tried to set up a tunnel Happy Eyeballs didn't work for me at all; almost everything went through the tunnel anyway and I had to deal with non-residential IP space issues and way too much traffic.

[jeroenhd]

ISPs won't bother with IPv6 until they've either run out of IPv4 space or the internet starts to use IPv6's advantages.

Discussions about IPv6 quickly end with "we have enough v4 space and there are no services that require v6 anyway". As long as the extra cruft for v4 support remains free or even supported, large ISPs won't care. We're at the point where people need to deal with things like peer to peer connectivity with two sides behind CGNAT which require dedicated effort to even work.

I know it sucks if none of the ISPs in your area support IPv6 and you're left with suboptimal solutions like tunnels from HE, but I think it's only reasonable all this extra cost or effort becomes visible at some point. Half the world is on v6, legacy v4-only connections are becoming the minority now.

[rjsw]

I have has native IPv6 since 2010, from two different ISPs.

It is also available for one of my phone contracts but not tried enabling it yet.

[mrjay42]

Well, you're very lucky (genuinely).

In 2025, I tried to access my services using IPv6 with 4G phones and different subscriptions (different ISPs), fact is, many (most?) of them did not support IPv6 at all :(

I had to revert to IPv4. And really I have nothing against IPv6, but yeah, as a simple user, self hosting a bunch of services for friends and family: it was simply just not possible to use only IPv6 :(

(for context, the 4G providers are French, in metropolitan France)

[rjsw]

My phone contract that does offer IPv6 is with Free, I could not work out whether it would disable IPv4 if I enabled IPv6 so have not tried changing it.

[ralferoo]

Conversely, I had IPv6 for about 5 years from an ISP and when I switched providers, the new ISP was IPv4 only. A few years later and they now support IPv6, but my firewall setup is now IPv4 only, so I've not bothered to update it.

[crawshaw]

(exe.dev co-founder here)

We are not running out of IPv4 space because NAT works. The price of IPv4 addresses has been dropping for the last year.

I know this because I just bought another /22 for exe.dev for the exact thing described in this blog post: to get our business customers another 1012 VMs.

[apitman]

Yep. As sad as it is for p2p, NAT handles most uses cases for users, and SNI routing (or creative hacks like OP) handles most use cases for providers.

I was surprised how low IPv4 prices have gotten. Lowest since at least 2019.

[crawshaw]

Amazingly even most p2p works with NAT, see (and I am biased here) Tailscale.

I certainly wish we simply had more addresses. But v4 works.

[apitman]

Your NAT traversal article is amazing, but sadly the long tail (ha) means any production quality solution has to have relays, which is a huge complexity jump for people who just want to run some p2p app on their laptop.

And it's not clear it will ever be better than it is now with CGNAT on the rise.

Would love to hear I'm wrong about this.

[rwmj]

Are there really ISPs that don't support IPv6? I've had IPv6 from various ISPs since around 2010, and even my phone gets an IPv6 address from the cellular network.

[TobTobXX]

Yes and it's ANNOYING. In Switzerland there is literally not one cellular network that issues IPv6 addresses. Also my workplace network (a school using some sort of Microslop solution) doesn't issue IPv6es.

I have a IPv6-only VPN with some personal services. Theoretically, the data can be transported via IPv4, but Android doesn't even query AAAA records if it doesn't have a route for [::]/0. So when I'm not home, I can't reach my VPN servers, because there is supposedly no address.

(I fix it by routing all IPv6 traffic through my VPN. Just routing connectivitycheck may suffice though).

[p_l]

Anything Microsoft lacking V6 is configuration issue - ever since Vista, Windows networking (in corporate) treats v4-only as somewhat "degraded" configuration (some time ago there was even a funny news post about how Microsoft was forced to keep guest WiFi with enabled v4, having switched everything else to V6 only)

[kiwijamo]

It varies in different parts of the world. Here in New Zealand all except one fixed line (i.e. fibre/xDSL) provider offers IPv6 (the only hold out being the ex-government telco). Wireless/mobile (4G/5G mobile or FWA) is a different story however as all wireless/mobile networks are IPv4 only still to this day (even thogh two of them are also fixed line providers offering IPv6 via their fixed line service!).

[doubled112]

Bell Canada does not provide IPv6 to Internet customers but their cell network does support it. They're one of what we call "the big three".

https://www.google.com/intl/en/ipv6/statistics.html#tab=per-...

Looks like Canada has roughly 40% adoption, and USA roughly 50% adoption.

[miyuru]

I complained as a yearly tradition for couple of years to get v6 enabled in my ISP. They had the core network enabled on World IPv6 Launch in 2012, but not deployed to end customers.

One simple way to check if your ISP have some kind of IPv6 netowork is to see if CDN domains given by YouTube and Facebook have AAAA records.

We shouldn't have to ask for ISPs to add IPv6 support but here we are.