r/ipv6

I've heard a lot of opinions as to how large of an IA_PD allocation is appropriate for a residential service. There's some consensus that /56 is (or should be) the standard, but what I see in practice is either a sole /64 (ew) or a /60 if the prefix hint is sent for that. IMO I have a hard time imagining a home customer using more than 16 /64s of GUA, but maybe I'm not *that* much of a power user...?

For the record, I've got three /64s out of the /60 I get from Xfinity (Main, Guest, and IoT). I'm presuming that 99% of residential customers just use a single /64, however, much like they only use one RFC1918 block for everything in their home.

Is the guidance to hand out a /56 documented in any RFCs, or is that just operator consensus?

EDIT: Note I'm referring to GUAs that are part of a PD allocated by an upstream, not internal/ULA addressing. I've got plenty of those myself.

How do I convince other people, for example, my friends, to enable IPv6 (assuming I know that their hardware supports it and that it is very simple to do)?

Since disabling IPv6 - my network is more reliable. Previously if there were issues with a broken path or degraded on either network, would just lead to intermittent delays, timeouts, failures. This is compounded with both v4 and v6 running. It adds complexity. So I disabled IPv6 and no longer have this. Recommended.

How can I do load balance with multiple upstream ISPs so I can control the data path when the packet passes the gateway?

Since one of the main goal for IPv6 is end-to-end connection, under this situation, how can I do load balance?

BGP isn't an option since I'm considering home user or small business user, who get their prefix directly from upstream ISP.

I am the admin for a small business with 4 isolated subnets that only talk to each other over the public internet.

There is no multihoming and each subnet has a static, public, ipv4 address. Sites are linked together with VPNs.

Our internal network is currently ipv4 only and I am looking to move to a dual stack network internally at all 4 sites.

This will be my introduction to ivp6 so I've been doing my reading and believe I need to setup ULA's in my network, but in my looking around online, those are contentious so I want a second opinion before I proceed.

My ISP does give me /56 prefix for my router to hand out GUAs to my internal network devices at all 4 sites.

But the two things that make me believe I need to also setup ULAs are:

-Internal DNS server that is not the router. From what I read, to use an internal DNS server for private, internal, DNS entries, you need ULA in order to be able to set a static IP to be handed out for the DNS server.

-I will not be able to register directly for a public ipv6, so I am dependent on my ISP's /56 they give me being static (well, unchanging) and I'm not sure I trust that. So I setup ULA's internally and then just have to update the routing (hopefully in one location per site) if the /56 my ISP gives me ever changes.

So, what are your thoughts? From a network design perspective anyways.

Do I need ULA's, or did I miss something and GUA's would suffice for my situation?

EDIT: To clarify, I meant running ULA internally along with GUA addresses, I am not talking about NATing my ULA addresses out to the public internet.

Skill issue

(and very, very old hardware/software).

From the article:

>IPv6 support continues to expand with automatic ISP dual-stack detection and WireGuard VPN over IPv6. For deployments operating behind CG-NAT, Teleport VPN helps maintain dependable remote access connectivity using our WiFiman client application or our UniFi Travel Router. However your ISP provides connectivity, UniFi is ready to help you make the most of your connection’s capabilities.

OK -- before I lose what little sanity I have.... this SHOULD work, but doesn't. Here is the netplan file I have for Ubuntu. Notice one IPv6 address is oommented out. It doens't matter which one I comment out, but if both are active, at random, only one works. If I comment out one, the other routes. I THOUGHT I had source routing rgiht.... I guess not.

network:
  version: 2
  renderer: networkd
  ethernets:
    enp4s0:
      dhcp4: false
      dhcp6: false
      addresses:
        - 10.0.1.2/16
        - 50.154.105.131/28
        - 199.181.204.131/25
        - 2001:55d:9080::0a00:0102/64
        #- 2602:805:A000::0a00:0102/64
      gateway4: 10.0.0.2
      gateway6: 2001:55d:9080::1
      nameservers:
        addresses:
        - 10.0.1.1
      routes:
        - to: default
          via: 50.154.105.129
          table: 100
        - to: default
          via: 199.181.204.129
          table: 101
        - to: default
          via: 2001:55d:9080::1
          table: 102
        - to: default
          via: 2602:805:A000::1
          table: 103
      routing-policy:
        - from: 50.154.105.128/28
          table: 100
        - from: 199.181.204.128/25
          table: 101
        - from: 2001:55d:9080::/64
          table: 102
        - from: 2602:805:A000::/64
          table: 103

What I THINK this says is (ignoring V4 which works), if the source address is 2602:805:A000::/48, route to 2602:805:A000::1. If it's 2001:55d:9080::/48 route to 2001:55d:9080::1. BUT....l.

This is Ubuntu 26.04 desktop. So if you want to win the Dodge Desoto with Groucho Marx, say the secret words here -- I've been saying a lot secret words, but it's frustrating so I can't say any of them in public.

Hello, I am noob in IPv6 and I was wondering if I could implement it in my homelab.

My ISP gave a IPv6 address /64 with no prefix delegation. Since I'm using a OPNsense as main Router, I've tried to enable RA but couldn't get any IPv6 in my LAN because apparently I don't have DHCP6-PD.

My LAN is on Track interface but still wouldn't work. Is it possible for me to have a IPv6 LAN with a /64 and no prefix delegation?

I’m developing a pure P2P application (without STUN/TURN or any other relay infrastructure) based entirely on IPv6 addressing. I’m looking for statistics about IPv6 adoption in mobile networks across different countries, as well as information about the properties of these networks.

What I specifically need:

- Country name

- Main mobile operators in the country (non-virtual operators only)

- Which operators provide IPv6 addresses

- Which operators allow incoming IPv6 connections on arbitrary ports >1023, and under what conditions

I’ll start:

Country: Russia

Main operators: MegaFon, MTS, Beeline, t2

Operators with IPv6: MegaFon, MTS

Allow incoming IPv6 connections:

- MegaFon (requires enabling the free “Open IPv6” service)

- MTS (works without additional conditions)

My English is very poor, so please use ChatGPT, another AI translator, or at least Google Translate to translate your replies into Russian. AI translators are usually more accurate.

Thanks in advance!

Has anyone actually gotten IPv6 to work with HA?

The official guide doesn't work. AI has no idea. I've spent hours trying to troubleshoot this.

I'm using static ipv6 with a /56

I can ping 2606:4700:4700:1111 from the opensense nodes, but I cannot get any connectivity to devices on any vlans.

I'm doing some work with NAT64/PREF64 on my network and there's something wrong with chromium based browsers in macOS.

To clarify, I don't use DNS64, just NAT64/PREF64 and CLAT manually enabled in macOS (by setting IPv4 to Off in Network settings). With this setup, CLAT works just fine, I have system level access (like ping) to IPv4 only addresses and Safari browser successfully accesses IPv4 only websites with the NAT64 prefix sent via PREF64.

Problem seems to be that Chromium based browsers seem to have their own DNS stack and they ignore the system level CLAT and just not load IPv4 only websites at all. If I enable DNS64 on my network, those browsers work just fine, but without DNS64 it's not sending the request to the system to synthesize the IPv6 address of the IPv4 only website.

This setup (CLAT/NAT64/PREF64 no DNS64) works just fine Linux (Fedora) with Chromium browsers, so there's definitely a flag or something that I can trigger in these browser to either synthesize the IPv6 themselves or just send the request to the system and let it do it (like Safari does).

Any ideas?

Have many legacy IPv4-only devices, and an IPv6-only upstream. Looking for an implementation of, or way to implement, NAT46+DNS46. Right now it seems Fortinet are shipping something packaged (the only ones in fact), but I'm looking for something I can set up on generic linux/FreeBSD.

CLAT/464xlat is explicitly out of scope because it requires cooperation on the PLAT side. Actual NAT46 translation is vastly preferable and would enable connections over IPv6 directly to IPv6-only hosts. To the rest of the world the network appears IPv6-capable, or at worst like a NAT66, and everyone can get on with their lives.

For those unfamiliar, NAT46/DNS46 is where DNS queries are received from IPv4 clients, the public IPv6 address is determined, and a temporary mapping between public IPv6 address and internal-use-only IPv4 address is created, allowing IPv4 clients inside to communicate with IPv6 hosts outside. (For those fretting about conflicts with existing public IPv4 addresses, the ones used in the mappings don't have to be globally routable. For those fretting about IPv6 addresses being larger than IPv4 address, this is translation not embedding, and few networks need enough simultaneous connections for this to be an issue.)

A userspace daemon or plugin for Tayga etc. etc. would be fine, it doesn't need to be implemented in-kernel.

edit: nevermind, guys. It's not my server that I'm reaching.

I have a server with a static IPv6 address. While troubleshooting some connection issues I found out that I can reach my server over the internet with just the subnet prefix followed by ::1, i.e. the server is reachable via 2001:ab1:1234:567::1. I thought that only zero blocks can be skipped like that (the full address contains no zeros). Does it mean that the subnet prefix itself is unique which makes it reachable? Can I use this abbreviated address everywhere instead of the full one, i.e. in AAAA records? Why does it work with ::1 but not other suffixes? What is special about ::1 in this case? Can I rely on the short address staying routable as long as the full one is? ip addr on the server shows the full address only on the interface.

I made a post several weeks ago, if IPv6 is enabled Google services do not work on iPhone's, Mac OS, iPads, etc. This affected google.com /Maps/ YouTube and the apps. But only with Apple devices.

The "fix" was to enable "auto" under HTTP proxy on Apple devices and it would fix it. But that is a non default setting.
Occured with both my UDM Pro & ISP provided Router.

Well... ISP reached out to me through reddit, and setup a visit to see it in person (They were slightly aware of the issue which affected a ton of their fiber customers).

Four ISP techs showed up, and two engineers that flew in from 2,000 miles away from corporate! They where at my house for right at 5 hours! Basically doing a lot of packet capture with an external device between the ONU WAN and the ISP router, along with going back and forth with someone over a call changing settings on the backend, they couldn't resolve it but captured a ton of data.

They said it seems to be related to QUIC. They said they would be sending it back to corp and also to Apple.

A week later I get a message asking me to turn IPv6 back on again to test.. And its now working normally!

I requested if they could tell me exactly what they found or changed, and will update here when I find out.

Now that is what I call ISP Support!