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I spent a week without IPv4 to understand IPv6 transition mechanisms

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Re: I spent a week without IPv4 to understand IPv6 transition mechanisms

#81
post #48

Earlier quoted context omitted.

Maybe you don't want to reveal your internal infrastructure to the world? Seems like basic opsec.

There's no chance of anybody guessing your infrastructure just by looking at your subnet. (Minimum is /64, which is HUGE!)

Every packet leaving an IPv6 network that isn't NATed has an effective node ID in the packet. No need to guess just look at the packets.

Re: I spent a week without IPv4 to understand IPv6 transition mechanisms

#82
post #40

Everyone always goes with the "You don't need NAT, everything is globally routable!" argument, as if that's something that anybody wants. Everything on my network is going to go through my firewall anyway. I don't want anything on my network to be globally routable. Of course, this is not a good reason to not use IPv6, don't get me wrong. It's a problem that's easy to overcome, I just think it's not a good way to get…

NAT and a Firewall are two different concepts. What's wrong with a firewall that blocks everything by default, yet all your devices have a public IP?

> NAT and a Firewall are two different concepts.

They are, but in practice they are muddled together and I suspect people are going to create subnets with IPv6 in the name of security. In IPv4 NAT is used to make sure your laptop isn't exposed to random script kiddies trying to scan for vulnerable services behind your router. A fun exercise is to plug a RaspberryPi up directly to a public facing IP address and log every packet it receives. Then give those scripts a few services to detect (HTTP server, SSH server, etc.) and look at how the traffic shifts from scanning for ports to scanning for vulnerabilities. Being connected directly to the public internet is a real eye opening experience.

I do believe future IPv6 networks will have gateway machines and/or bastions that are connected to the public internet with public IPv6 addresses. And then they'll have an interior network that they use NAT for. Individual machines will not be routable or discoverable without going through a bastion/gateway that explicitly controls the flow of traffic into a network. Not because this is the ideal way to structure an IPv6 network, but because this pattern is going to carry over from the IPv4 world and there is a lot of momentum in tribal knowledge using NAT as a form of firewall.

Re: I spent a week without IPv4 to understand IPv6 transition mechanisms

#84
post #78

Question from a (relative) IPv6 newbie that wasn't addressed in TFA: Let's say I have a very small home lab. I have a handful of hosts that get their IP addresses via DHCP from my router. In the router, DHCP and DNS are tightly coupled such that the router essentially always knows the MAC address, IP address and hostname of each device. Now I want to run IPv6 on this network as a first-class citizen. Since DHCPv6 is…

In what way is DNS and DHCP tightly coupled? Automatically creating A records for DHCP hosts is not normal in my experience, especially for consumer routers. If some device your using supports this it could work for IPv6 as well as devices will broadcast on the network for routers when using SLAAC I believe.

Re: I spent a week without IPv4 to understand IPv6 transition mechanisms

#85
post #72

I'd love to embrace ipv6, but my ISP's official line, for as long as I can remember, is 'planning it, details to come'. I don't expect them to move forward on it until significant sites become ipv6 only as they've admitted that they have more than enough ipv4 addresses for their subscriber base, so there's very little incentive for them to do anything atm.

You can request free IPv6 connectivity through the Hurricane Electric tunnel broker at ipv6.he.net

Thanks, I've actually looked at that in the past, but I'm not sure what their throughput is, and I'd have to configure each device individually as the router I have can't be configured for it.

I think I've still got my HE IPv6 t-shirt somewhere, from when I completed their readiness quiz so years ago!

Edit: I actually decided to set up a tunnel, just to see how well it worked, and it turns out my ISP supplied router won't forward the protocol 41 packets anyway, so that's a total no-go.

I suppose I could probably set up a small VPS and Wireguard vpn, then forward the IPv6 packets that way?

Re: I spent a week without IPv4 to understand IPv6 transition mechanisms

#86

Everyone always goes with the "You don't need NAT, everything is globally routable!" argument, as if that's something that anybody wants. Everything on my network is going to go through my firewall anyway. I don't want anything on my network to be globally routable. Of course, this is not a good reason to not use IPv6, don't get me wrong. It's a problem that's easy to overcome, I just think it's not a good way to get…

> I don't want anything on my network to be globally routable. Then... don't route anything on your network. NAT is address translation, not routing. NAT makes it difficult for you to host services on your network, forcing dependency on cloud services, and when ISPs do it (CGNAT), it makes it just about impossible unless you want to thread your traffic back through a third-party service. If you want a good chance of…

With NAT it is impossible to make a mistake that causes machines with a private address to become reachable to the internet. That is a reality that is not going anywhere, no matter if you like it or not, no matter if you think it is stupid or not.

Re: I spent a week without IPv4 to understand IPv6 transition mechanisms

#87

Why should I spend the time and energy to deal with IPv6 when disabling it fix many issues ? The listed advantages are not worth the troubles in my experience.

Increased number of available IP addresses, improved security features, simplified network management, reduced network complexity, and support for new technologies. The adoption of IPv6 will lead to cost savings, improved network performance, and increased scalability. Scalability may not matter in the typical home network, but in an enterprise environment, the cost of up-keeping the network backbone is significant.

>simplified network management

I keep hearing this, but it doesn’t seem more simple to me. My ISP won’t reserve me a /48, so I can’t control the management ips of devices on my network. The solution is apparently to set up dynamic dns, which I have no interest in doing.

Re: I spent a week without IPv4 to understand IPv6 transition mechanisms

#88

I have built a couple of dual stack Kubernetes clusters already and they work much better to be honest. Most of the problems are solved and especially for node-based-ranges it works really well. Even in ipv6 only mode calico will manage amazingly and so do my OpenWRT routers. HOWEVER, My ISP regularly messes up with its ipv6 routing (deutsche Telekom (so as big as it can get for me) and if that's not the problem, the…

> My ISP regularly messes up with its ipv6 routing

Can you expand on this? I recently upgraded my network to support ipv6 but a big concern I have is what if they (Verizon Fios) change my assigned block? How can I make sure my PI hole and server has the same static IP address?

Re: I spent a week without IPv4 to understand IPv6 transition mechanisms

#89
post #72

I'd love to embrace ipv6, but my ISP's official line, for as long as I can remember, is 'planning it, details to come'. I don't expect them to move forward on it until significant sites become ipv6 only as they've admitted that they have more than enough ipv4 addresses for their subscriber base, so there's very little incentive for them to do anything atm.

My ISP went "we're planning it", "it's in progress", "we cancelled it", "there's not enough demand", and they're a pretty large ISP in my country.

Re: I spent a week without IPv4 to understand IPv6 transition mechanisms

#90
post #78

Question from a (relative) IPv6 newbie that wasn't addressed in TFA: Let's say I have a very small home lab. I have a handful of hosts that get their IP addresses via DHCP from my router. In the router, DHCP and DNS are tightly coupled such that the router essentially always knows the MAC address, IP address and hostname of each device. Now I want to run IPv6 on this network as a first-class citizen. Since DHCPv6 is…

It's not usual for your router to create A or AAAA records for the hosts connected to it. Look into Multicast DNS.
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