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Tell HN: IPv6-only still pretty much unusable

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Re: Tell HN: IPv6-only still pretty much unusable

#461

Post by justin_oaks »

Arnavion wrote: post #384
justin_oaks wrote: post #237

Earlier quoted context omitted.

Thanks, that helps a lot. This got me reading about IPv6 again. I'm trying to figure out how we'd set up an IPv6 network in the case where we have 1) Two upstream ISPs, mostly for failover, but could be loadbalanced too. 2) Internal servers with assigned DNS My initial thoughts were that for each of the two ISPs, each host (e.g. personal desktop or laptop) would use the IPv6 prefix and end up with two addresses. But…

If you want failover-independent IPs you can keep using NAT, ie NPTv6, at the gateway level and not bother with giving public IPs to your LAN machines.

That's possible, but my understanding is that NPTv6 is strongly discouraged. Part of the point of IPv6 is do away with NAT and the problems caused by it.

I was hoping there was a better way.

Re: Tell HN: IPv6-only still pretty much unusable

#462

Post by justin_oaks »

argulane wrote: post #28
justin_oaks wrote: post #14

Having "grown up" with IPv4, I'm slow to learn everything necessary to set up an IPv6 infrastructure. The times I did look into it, IPv6 seemed so much more complicated than IPv4, but maybe that's just because I'm just not familiar with it. Are there any good resources on setting up IPv6 support from first principles? I still get confused as to the "right" way to set up internal networks for IPv6, especially when DHC…

Everything should get its IPv6 configuration via SLAAC. DHCPv6 is only useful when you plan to provide prefix delegation for extra routers or network boot information.

How does that work you have more than one ISP giving you an IPv6 prefix?

Re: Tell HN: IPv6-only still pretty much unusable

#463

Post by justin_oaks »

justin_oaks wrote: post #291
stevefan1999 wrote: post #73

Earlier quoted context omitted.

just a funny joke: what about using IBGP/OSPF for prefix delegation?

How does that work you have more than one ISP giving you an IPv6 prefix?

Oops. Meant to reply to parent. Now I can't delete the comment.

Re: Tell HN: IPv6-only still pretty much unusable

#465

Post by solarkraft »

throw0101a wrote: post #164
redox99 wrote: post #32

IPv6 has been one of the biggest failures in the last couple of decades. And I don't mean adoption, I mean the standard itself. If IPv6 were IPv4 with more octets, then we would all have been using it for like a decade. Yes, I understand it would still require some breaking changes, but it would have been a million times easier to upgrade, as it would be a kind of superset of IPv4 (1.2.3.4 can be referred as 0.0.0.0.…

> And regarding compatibility, with ipv4+ if you have a 0.0.0.0.x.x.x.x ip address you would be able to talk to both ipv4+ aware and legacy ipv4 devices natively without any tunneling (because you also own the legacy, non quad 0 ip address). This exists: > Addresses in this group consist of an 80-bit prefix of zeros, the next 16 bits are ones, and the remaining, least-significant 32 bits contain the IPv4 address. For…

> What makes you think that companies would have been willing to make the effort to deploy "IPv4+" any more than IPv6?

That it's much easier to set up.

Re: Tell HN: IPv6-only still pretty much unusable

#466

Post by ipython »

zhoujianfu wrote: post #407
redox99 wrote: post #32

IPv6 has been one of the biggest failures in the last couple of decades. And I don't mean adoption, I mean the standard itself. If IPv6 were IPv4 with more octets, then we would all have been using it for like a decade. Yes, I understand it would still require some breaking changes, but it would have been a million times easier to upgrade, as it would be a kind of superset of IPv4 (1.2.3.4 can be referred as 0.0.0.0.…

I always thought to start they should have just allowed each octet two-ish more bits, so you could have 999.999.999.999. I know it’s the hackiest of all hacks, but it sure would have been an easy upgrade from the software perspective. And it would have given about a 256x increase in the number of ips. Which I kinda think actually might have served us for a long time.

And where do those two extra bits go? How do existing routers that don’t know anything about two extra bits route those packets? Here’s the ip packet header: https://commons.wikimedia.org/wiki/File:IPv4_Packet-en.svg

Re: Tell HN: IPv6-only still pretty much unusable

#467

Post by chillfox »

throw0101a wrote: post #300
theamk wrote: post #259

Earlier quoted context omitted.

Mayne RFC exists, but it os not used in teal world anywhere. In all servers, I configure IPv4 and IPv6 separately. Network setup is separate. DHCP daemons are separate. Firewall rules are separate. Network monitoring is separate. I would switch to that "IPv4+" system if it existed.. I am willing to use latest software/standards to future-proof my setup, but duplicating all the work is too much for me.

> I would switch to that "IPv4+" system if it existed.. I am willing to use latest software/standards to future-proof my setup, but duplicating all the work is too much for me. And exactly how would you accomplish this switch to a larger address space? Please explain the steps exactly how they would be done. Because IPv4 has 32 bits of address. Anything after IPv4 needed >32 bits of address. How exactly do you fit in…

There's a huge difference in the effort required of maintainers (both actual work and cognitive) from just upping the integer size vs what IPv6 is.

Re: Tell HN: IPv6-only still pretty much unusable

#468

Post by solarkraft »

RijilV wrote: post #9

It's been a quarter of a century since IPv6 launch. There's some really good lessons learned here. IPv6 requires everyone, everywhere, needs to change their configuration to add IPv6 addresses and network connectivity to every node/endpoint. The madness of course is that all the underlying infrastructure software (routers, OS, standard libraries) all support IPv6. It would seem, at a large enough scale, that software…

If it was easy to set up, the providers would just include it (or the price would be low enough to shrug it on).

But it's not really trivial and IPv4 works well enough for most people to bother. Remember the typical workaround for network issues being disabling IPv6?

Re: Tell HN: IPv6-only still pretty much unusable

#469

Post by anyfoo »

Dagger2 wrote: post #413
anyfoo wrote: post #379

Earlier quoted context omitted.

Yeah, but I have to say, even as someone who wants IPv6 to succeed and supersede IPv4, from the perspective of building that network infrastructure software, I think this "IPv4+" would have been massively simpler to add, extremely so, and that may have aided adoption a lot. It's really hard to overstate how much simpler tacking on 128bit IP addresses to an otherwise unmodified protocol would have been in the software…

The majority of the problems seem to come from the fact that v6 addresses are longer than v4 ones. That's why we need socket(AF_INET6)s and AAAA records and a DNS API that supports multiple address families and dual stack and new firewalling and updates to all protocols that embed v4 addresses. You're going to have the exact same problems with any protocol that has addresses longer than v4's.

I find that hard to believe. That may be true for endpoints, but I'm talking about the network infrastructure in between. There, I believe that the vast differences in the protocols on higher level (autoconfiguration, link-local addresses, temporary addresses, Neighbor Discovery as part of ICMP6 instead of ARP, ICMP6 itself, and so on and so forth) are much, much more work to implement than dealing with new DNS records and APIs, and the new struct sockaddr variants.

My point is exactly that I have a strong suspicion that the longer addresses are not the problem for slow adoption, the different network protocols and semantics are.

Re: Tell HN: IPv6-only still pretty much unusable

#470

Post by ipython »

howinteresting wrote: post #100
Dagger2 wrote: post #70

Earlier quoted context omitted.

I'm not sure it was ever relevant. All it does is describe the problem, which was already well-known at the time by the people working on v6. It doesn't give a fix for it. It doesn't give a fix because no fix is possible. Because the problem comes from the design of v4, not from v6. For some reason djb wasn't able to get his head around that, and people have been pointing to that damn page as if it's some big gotcha…

I mean, v6 is still mostly a failure, so (rightly or not) the situation is going to be blamed on the people that have been pushing v6. That's just the cost of trying to push the entire world towards a new standard. (I know that v6 has been a success within datacenters and such.)

Actually, aws and the big cloud providers are only now starting to release ipv6 aware services.

If close to half of US traffic to google transits over ipv6 is considered a failure, I would hate to see “success”.

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