5 ms·

> or just bite the bullet and use ULA. This is the proper ipv6 solution. With ipv6, one ethernet interface is _supposed_ to have multiple addresses. You would

> or just bite the bullet and use ULA. This is the proper ipv6 solution. With ipv6, one ethernet interface is _supposed_ to have multiple addresses. You wouldn't want your lan routing to stop working when your ISP goes down, right? So configure your internal DNS with ULA (which should be stable for each machine for a given prefix, even with SLAAC) and be done with it, much like internal DNS using private addresses in ipv4. For externally visible servers, do the normal thing, that is, those servers dynamically update global dns, much the same way with ipv4 dyndns. Another learning curve for ipv6 is that people get frustrated by dynamic prefixes, but it's the nature of residential networks: the ISPs want a stateless solution, so customers get a dynamic prefix. Maintaining the same prefix across power outages needs a stateful solution, so only business plans offer them for an extra fee, much like static ipv4 addresses. And we've had dyndns for decades now for exactly that use case. Just keep using that.

lloeki 2y ago
> the ISPs want a stateless solution, so customers get a dynamic prefix. Maintaining the same prefix across power outages needs a stateful solution, so only business plans offer them for an extra fee, much like static ipv4 addresses. I'm surprised based on my experience: in 15 years of residential IPv6 usage I've always had the same IPv6 prefix (for a given ISP contract of course), even for those ISPs that insisted on handing out dynamic IPv4 with no option for a static one plus had no qualms renewing the IP at any moment, not just power down. > stateful solution I'm seeing this the other way around: dynamic needs lease tracking while static just needs a permanent record attached to the already present auth mechanism.
- hairyplanter 2y ago
  My experience is the opposite!
- eythian 2y ago
  My ISP-given IPv6 (/57 for whatever reason) prefix is also stable, however beware that, at least on my OpenWRT based router, the option to release the prefix back to the ISP when the router is shut down is checked by default. I discovered this when I rebooted for a firmware update and when it came back up my network had renumbered itself.
- FireBeyond 2y ago
  > in 15 years of residential IPv6 usage Out of curiosity, what residential ISPs were handing out IPv6 15 years ago?
  - ac29 2y ago
    Comcast started rolling out IPv6 in 2011
  - lloeki 2y ago
    Can't recall the exact timeline but: - I think Free had it since forever and a half, although IIRC it was some weird 6rd or something. Freebox v6 (2011) for sure had it, v5 (2006) may had supported it from the start and for sure supported it down the road, I think v4 could have had it too through an update at least but honestly can't recall. - Orange in France had a public opt-in experiment for native IPv6 over ADSL to which I enrolled at the time. - Then I lost IPv6 because I moved to a cable operator which did not support DOCSIS 3.0 (a requirement for IPv6 on cable connections) at the time. - After that FTTH rolled out and basically every ISP provided native IPv6 on it from the get go. Non-biz IPv6 support in France is sitting in the ballpark of 99% these days, both residential and mobile. National regulations helped a lot. Residentially there has been a huge plan towards a national FTTH rollout, including in remote areas (the idea being that no one should be cast aside of a full speed internet); this plan also had specific requirements to enforce competition to prevent regional or local monopolistic situations such as the one that historically happened with cable operators (or like the ones I keep hearing about in the US). For mobile it was simpler: you want a radio license for 5G? you have to support IPv6, or else.
krylon 2y ago
I never heard of ULA before, and it sounded a bit overwhelming at first. But on a Fritz!Box with recent firmware, it's very easy to enable, and voila! - just works.
- simoncion 2y ago
  Yep! ULA should be thought of as the IPv6 equivalent of RFC 1918 space... with the added bonus that -unlike with IPv4- ULA prefixes are very unlikely to collide, so merging internal networks will very rarely require renumbering.
OJFord 2y ago
What's the point of using IPv6 at all on a home network if you use ULA though? If you continued to use an IPv4 setup you were familiar with but allowed your router to talk both or v6 only, wouldn't it be the same? Is it that you'd still have the globally addressable addresses on NICs with a ULA too, just that's not what you'd use for routing internally? (Not that I'm really sure of the benefit of that residentially either?)
- the8472 2y ago
  With ULA you generate a random prefix which means it's extremely unlikely there's a collision. So no need for internal NATing or interface disambiguation because a machine is connected to two networks (e.g. via tunnels) that are both using 192.168.0.0/24. Which also means less book-keeping for collision avoidance. Just roll the dice.
Dylan16807 2y ago
> Maintaining the same prefix across power outages needs a stateful solution, so only business plans offer them for an extra fee, much like static ipv4 addresses. Whose power outage? The ISP needs to reliably track allocations despite some of their equipment going out, except in the extreme edge case of their entire operation cold starting. If the client modem goes out it can just be told the same number again when it boots. And that's not even getting into how trivially small this amount of information is to save to disk. Non-persistent allocation has technical benefits when your devices keep moving between nodes or when they're offline most of the time. Otherwise not so much.

lloeki 2y ago

> the ISPs want a stateless solution, so customers get a dynamic prefix. Maintaining the same prefix across power outages needs a stateful solution, so only business plans offer them for an extra fee, much like static ipv4 addresses. I'm surprised based on my experience: in 15 years of residential IPv6 usage I've always had the same IPv6 prefix (for a given ISP contract of course), even for those ISPs that insisted on handing out dynamic IPv4 with no option for a static one plus had no qualms renewing the IP at any moment, not just power down. > stateful solution I'm seeing this the other way around: dynamic needs lease tracking while static just needs a permanent record attached to the already present auth mechanism.

hairyplanter 2y ago
My experience is the opposite!
eythian 2y ago
My ISP-given IPv6 (/57 for whatever reason) prefix is also stable, however beware that, at least on my OpenWRT based router, the option to release the prefix back to the ISP when the router is shut down is checked by default. I discovered this when I rebooted for a firmware update and when it came back up my network had renumbered itself.
FireBeyond 2y ago
> in 15 years of residential IPv6 usage Out of curiosity, what residential ISPs were handing out IPv6 15 years ago?
- ac29 2y ago
  Comcast started rolling out IPv6 in 2011
- lloeki 2y ago
  Can't recall the exact timeline but: - I think Free had it since forever and a half, although IIRC it was some weird 6rd or something. Freebox v6 (2011) for sure had it, v5 (2006) may had supported it from the start and for sure supported it down the road, I think v4 could have had it too through an update at least but honestly can't recall. - Orange in France had a public opt-in experiment for native IPv6 over ADSL to which I enrolled at the time. - Then I lost IPv6 because I moved to a cable operator which did not support DOCSIS 3.0 (a requirement for IPv6 on cable connections) at the time. - After that FTTH rolled out and basically every ISP provided native IPv6 on it from the get go. Non-biz IPv6 support in France is sitting in the ballpark of 99% these days, both residential and mobile. National regulations helped a lot. Residentially there has been a huge plan towards a national FTTH rollout, including in remote areas (the idea being that no one should be cast aside of a full speed internet); this plan also had specific requirements to enforce competition to prevent regional or local monopolistic situations such as the one that historically happened with cable operators (or like the ones I keep hearing about in the US). For mobile it was simpler: you want a radio license for 5G? you have to support IPv6, or else.

krylon 2y ago

I never heard of ULA before, and it sounded a bit overwhelming at first. But on a Fritz!Box with recent firmware, it's very easy to enable, and voila! - just works.

simoncion 2y ago
Yep! ULA should be thought of as the IPv6 equivalent of RFC 1918 space... with the added bonus that -unlike with IPv4- ULA prefixes are very unlikely to collide, so merging internal networks will very rarely require renumbering.

OJFord 2y ago

What's the point of using IPv6 at all on a home network if you use ULA though? If you continued to use an IPv4 setup you were familiar with but allowed your router to talk both or v6 only, wouldn't it be the same? Is it that you'd still have the globally addressable addresses on NICs with a ULA too, just that's not what you'd use for routing internally? (Not that I'm really sure of the benefit of that residentially either?)

the8472 2y ago
With ULA you generate a random prefix which means it's extremely unlikely there's a collision. So no need for internal NATing or interface disambiguation because a machine is connected to two networks (e.g. via tunnels) that are both using 192.168.0.0/24. Which also means less book-keeping for collision avoidance. Just roll the dice.

Dylan16807 2y ago

> Maintaining the same prefix across power outages needs a stateful solution, so only business plans offer them for an extra fee, much like static ipv4 addresses. Whose power outage? The ISP needs to reliably track allocations despite some of their equipment going out, except in the extreme edge case of their entire operation cold starting. If the client modem goes out it can just be told the same number again when it boots. And that's not even getting into how trivially small this amount of information is to save to disk. Non-persistent allocation has technical benefits when your devices keep moving between nodes or when they're offline most of the time. Otherwise not so much.