Discussion
Building a Mostly IPv6 Only Home Network
para_parolu: I can’t understand benefits of having ipv6. The only one is public ips but rest is just headache. In my home network I specify disabled v6 everywhere.
baq: It doesn’t matter in home networks, it’s a major pain in the ass if you are a Fortune 500 company and want to set up more intercompany vpn links
mwexler: Finally. I will now be able to run ~340 undecillion devices on my home network. I'll have the smartest "smart home" on the block.
mr_mitm: A site-to-site VPN of two previously unrelated local networks is a pure gamble with IPv4. It would be almost straight forward with IPv6.
dwedge: I never understood the rationale of giving out /64 and /48 like candy after what happened with ipv4. I know it's still a massive increase in capacity and I know it makes the networking easier but it seems like we went from something that definitely won't run out (ipv6 addresses) to something that probably won't (number of /48 ranges)
ndriscoll: /48s are "small" enough that we could give ~8 billion people each 35,000 of them, and we'd still have ~1.5 trillion left over.
rao-v: I messed with this at one point and gave up when I realized every device would have a permanent externally addressable IP within a block that is basically linked to me (good luck trying to change your IPv6 /48 every month or whatever you get with consumer IP addresses)It’s probably not a big deal and NAT etc. is no protection but it gave me the heebie jeebies.
webstrand: IPv4 pricing isn't a good enough reason? If all of my devices had nice ipv6 connectivity I could ditch the public ipv4 addresses, but I have to keep them so that my ipv4-only devices can still reach them.
iknowstuff: Ipv4 is the headache. What are you talking about, ipv6 is simpler in my experience.
chungy: IPv4 is pretty simple and good for LANs. Nothing wrong with sticking to it.
iknowstuff: Matter requires IPv6
victorbjorklund: Wish I could use ipv6. My ISP doesn’t support it (yea, I know tunnels exists but then it’s just more pain than just using ipv4)
jcalvinowens: Do you actually own that /48? The problem with using the globally routable addresses internally is that your public /48 might change in the future, and and that will force you to change a bunch of internal stuff.I have my router set up to advertise two /64 prefixes on each LAN subnet: one from fddd:deca:fbad::/56* that I use for all internal communication, and one from 2001:5a8:xxxx:xxxx:/56 that is only used for talking to the internet. Every device I've ever tested supports this configuration flawlessly, including a 10+ year old VoIP phone.My router is a Linux PC, so I can configure radvd however I want. Maybe home routers won't let you do this.* You're supposed to pick a random prefix in fd00::/8 but uniqueness only matters if you intend to merge networks with somebody else later, I care more about it being easy to remember.
flumpcakes: In IPv6 the smallest 'subnet' is /64 if I recall correctly.It's weird having a subnet size equal to a complete IPv4 Internet worth of IPv6 Internets but I believe the rationale was that you would never in practise run of out IPs in your subnet. A lot of Enterprise IPv4 headaches are managing subnets that are not correctly sized (organic growth, etc.). IPv6 is always routable for the same reason (companies reusing RFC1918 making connecting networks a pain).There are different headaches with IPv6 - such as re-IPing devices if they move subnet - i.e. move physical location, or during a failover etc.I'm not sure what the best practise there is as many enterprises don't use IPv6 internally. In my experience anyway.
boredatoms: If we actually get to the point of address shortages,Either, NATv6 would become a thing, or instead I hope SLAAC would get deprecated and dhcpv6 would become mandatory so we could give out smaller than /64s
tosti: Current recommendation (afaict ianant) for ISPs is to give everyone a /56. Not every isp does that, ofc
arhue: For home use biggest advantage is that it avoids NAT, which breaks end to end connectivity. Lot of services use hacks to try to mitigate broken connectivity.
compounding_it: >Do you actually own that /48?In my experience the ISP generally fixes a /64 for each customer. So if in the future you change your ISP, you might want to keep the remaining addresses same while just using a script to replace the preceding /64 address.
jcalvinowens: Typically it's similar to ipv4, they try to assign the same address/prefix for the same MAC/DUID. The most common reason to lose your addresses is replacing your router. Hopefully new routers allow you to set the dhcpv6 DUID somehow...
compounding_it: I haven't experienced this. For me it's statically assigned but my guess is that the PON serial and/or MAC is being used or the customer ID. I think the ISPs have gotten very automated these days and everything seems to be some sort of SDN. It saves lot of labour hours in troubleshooting like customer forgetting their wifi passwords to their routers.
kccqzy: My ISPs change the /64 more often. So I use the ULA a lot more often. My router runs its own DNS server and then it advertises this DNS server using a ULA address.
compounding_it: video games
boredatoms: It looks like an in-kernel replacement for jool is cominghttps://lore.kernel.org/netdev/20260319151230.655687-1-ralf@...
lucasay: IPv6 isn’t that compelling on a simple home network, but avoiding NAT and easier end-to-end connectivity are pretty real advantages.
wolvoleo: Yes. I wish they had simply used a more sane address length instead, and maybe given everyone 65535 addresses at most. More than enough for the craziest home lab ever.Really, just adding 2 bytes to IPv4 would have fixed everything and made it a lot simpler to move over. IPv6 is overkill and I think that really hurt its adoption. I remember being at uni and being told "this is the next big thing". In 1993. And it's not even a big thing now.
teraflop: I can think of at least two reasons why this isn't worth worrying about.One is quantitative: you have to remember that 2^48 is a much much bigger number than 2^32. With 2^32 IPv4 addresses, you have about 0.5 addresses per human being on the planet, so right away you can tell that stringent allocation policies will be needed. On the other hand, with 2^48 /48 ranges, there are about 8,000 ranges per human being.So even if you hand a few /48s out free to literally everyone who asks, the vast majority will still be unallocated. A /48 is only about 0.01% of what could be said to be a "fair" allocation. (And yet, a /48 is so huge in absolute terms that even the vast majority of organizations would never need more than one of them, let alone individuals.)The other is that unlike, say, the crude oil we pump out of the ground, IP address ranges are a renewable resource. If you hand out a free /48 to every person at birth, then long before you start running out of ranges, people will start dying and you can just reclaim the addresses they were using.
jcalvinowens: Interesting. Honestly I like having control over it, that would annoy me. I deliberately change the DUID in dhcpcd to force my public addresses to change every so often.
wolvoleo: Why though? What's the problem with ipv4?I find it much simpler for troubleshooting etc to have simple IPv4 addresses. But cool that it can be done :)I've switched off IPv6 on my router anyway, I haven't yet needed it. My provider didn't offer it last time I checked but when they do enable it I don't want it suddenly popping up against an untested router configuration.
dijit: I don't know your background, but I find that the people who feel that there's nothing wrong with IPv4 have never done any work with UPNP or NAT. For them it's always "just worked" and they don't recognise what pain has gone into trying to keep it working well despite our usage of it bordering abusive.NAT is the devil.If anyone replies to this with the myth that NAT is a security mechanism I will firmly, yet politely, point them to a network development course because they don't know what they're talking about and I'm sick of hearing it. It's not true, I will not entertain this falsehood anymore.
mrsssnake: > able to run ~340 undecillion devices on my home networkYou now can have these devices connected to network called Internet.Unlike IPv4 were the number of devices on the Internet in home network is one (the main router) or zero (in case if CGNAT) and the others just pretend.
mrsssnake: This video summarizes it nicelyhttps://www.youtube.com/watch?v=42Hy4JtBeQA
wolvoleo: Huh, I have matter devices working here and IPv6 is off on my router and DHCP. And on home assistant too which does the matter router. Does it use link local or something?
