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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

#301

Post by pantalaimon »

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.

You can even do prefix delegation with SLAAC, although not really in a standard way

https://doc.riot-os.org/group__net__gnrc__ipv6__auto__subnet...

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

#302

Post by ipython »

justsomehnguy wrote: post #221
est31 wrote: post #157

Earlier quoted context omitted.

One of the ideas of ipv6 was to reduce routing tables, those tables that backbone providers have to keep in memory and look up for incoming traffic. With ipv4's fragmented allocation scheme, these routing tables are huge. With ipv6, even huge companies like amazon only have a couple of global allocations. A "ipv4 with more octets" scheme would have kept that fragmentation around. That being said, Amazon currently has…

> Amazon currently has 2880 ipv4 allocations and 946 ipv6 allocations... not much gained I guess? Whole IPv4 address space is 4294967296 addresses. A single /48 is 1,208,925,819,614,629,174,706,176. And 2804:800::/32 is 79,228,162,514,264,337,593,543,950,336.

Gp comment refers to the number of routing table entries, not total number of addressable ips.

Ideally the number of ipv6 allocations should be close to 1 rather than close to 1000.

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

#303

Post by jeroenhd »

jedberg wrote: post #278
jeroenhd wrote: post #266

Earlier quoted context omitted.

If it's just "The IT guy", then IPv6 will work out of the box for outgoing traffic and will block all incoming traffic. This is why almost half of the USA is using IPv6 right now, it's just turned on by default. Hosting stuff is harder, but it's also that different. Theoretically, you can NAT IPv6 traffic to an IPv4 server inside your network no problem, but it's a pain and nobody really needs it anyway, so it's not…

I think you're missing the point. You're a network engineer and know what you are doing. Most people aren't. IP4+ would be easier because it's more incremental and less change than IPv6. Yes, there exists solutions to all the problems that IP4+ would solve, but the point is backwards compatibility and incremental change is always easier than doing something new.

But, correct me if I'm wrong, IP+ doesn't do anything differently from IPv6, except that it changed the 6to4 prefix?

Host 1.2.3.4.5.6.7.8 still can't communicate with a "legacy" host 4.5.6.7 without some kind of bidirectional translation mechanism. Just prepending 0.0.0.0 to an address (or 2002:c000:0204, for that matter) doesn't fix the problem.

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

#304

Post by gurrone »

cadence- wrote: post #20

I’m still waiting for Amazon to start supporting Elastic IPv6 in their AWS.

That just made me look at Google Cloud again, and it's depressing to see. At least some types of load balancer do support dual-stack setups, but not if you configure them via GKE with the k8s ingress controller. If you use that one you're out of luck and they maybe now implement it for the new gateway API controller. So if you use GKE and ingress you can configure two of them. One with a static v4 address and another one with a static v6 address. Of course you pay twice then.

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

#305

Post by ipython »

codegeek wrote: post #282
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 joke with "We figured out how to move from Python 2 to 3 but we still cannot figure out how to do IPv6" :). What a catastrophic failure it has been. Should we just stop using it altogether and retire or are there people still advocating ?

Yes, people are using ipv6 for real deployments. See any large scale mobile network deployment. Funny thing is most people never realize because it all just works…

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

#306

Post by tjohns »

jeroenhd wrote: post #294
tjoff wrote: post #179

Earlier quoted context omitted.

Literally the post I answered. Fact: SLAAC does not do DNS. So, my question then is: how do you do DNS? Answer: "The SLAAC should not change after the host has generated it during installation / first connection, as long as you don't reinstall the OS etc." Since SLAAC does not do DNS that answer implies that you'd enter it during connection/installation to complete the config.

SLAAC installations can use RDNSS to configure DNS. Windows, according to Wikipedia, doesn't support it, but if you want to please Microsoft there's stateless DHCPv6 (which does not maintain leases, configure addresses, or do anything else that SLAAC doesn't do already; it can be simple piece of software in comparison). On the other hand, Android and ChromeOS don't support DHCPv6 for DNS server provisioning because o…

Windows supports SLAAC+RDNSS, as long as you're running Windows 10 or newer.

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

#307

Post by acdha »

Yuyudo_Comiketo wrote: post #289

All ipv6 shortcomings discussion aside; What I think is the more vital problem to focus on is that the governments clearly don't want us mere mortals to expose our own servers running on our own hardware to the outside world (most often justifying that with "it's for your own security" mantra, for we're all deemed too dumb to figure that out for ourselves). ISP-imposed ipv4 double NAT (imposed on ISPs by the governme…

This seems like a poorly-researched conspiracy theory. Nobody is forced to use double-NAT, and if there was some secret policy which somehow has avoided leaking for a couple of decades, you'd think they'd have blocked IPv6 deployments, too.

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

#308

Post by ipython »

nottorp wrote: post #263
yesco wrote: post #122

Earlier quoted context omitted.

A confusing aspect of IPv6 is that it's actually a much simpler protocol than IPv4, you often end up assuming you need to configure a bunch of stuff that you really don't have to. The most common example would be NAT, despite the complexity it adds to IPv4, people often get comfortable with idea of setting up complex subnet hierarchies and feel lost when that all just disappears with IPv6. The key things to remember…

Ok, i'll bite. > Auto generated addresses are usually in the form of "prefix - device_id" so even if a node has a lot of addresses, they are all mostly the same > Internet/non-local IPv6 addresses break the rules a bit and don't use a device_id in their addresses in order to protect user privacy So a device needs to have both an internal address and an "Internet/non-local" address in IPv6? Plus one for WAN and Link-L…

Actually there can be an arbitrary number of addresses per device, thanks to the privacy extensions. Since your “device id” is a simple derivation of your MAC address, technically you could be tracked across ipv6 networks through that.

Therefore most modern oses will create a time limited random address (within the prefix) to use. When the connections using that address have died, the address is retired. New addresses are generated on a periodic basis. So if you have long lived connections you could have several active privacy addresses at the same time.

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

#309

Post by ipython »

tjoff wrote: post #185
tjohns wrote: post #142

Earlier quoted context omitted.

What? No. You connect a device, and SLAAC (and optionally DHCPv6, on enterprise networks) configures everything. It just works. SLAAC is more than capable of sending DNS settings to devices. There's no manual configuration involved.

My post said to use DHCPv6 and RDNSS. Follow up claimed to use SLAAC instead. SLAAC does not do DNS. Clear as day?

I run dual stack at home and every device I have connected to my home network runs ipv6 with no manual configuration whatsoever. It’s easier than ipv4 when you consider providing inbound access to resources (no nat configuration)
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