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IPv6-only Network based on Jool

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Re: IPv6-only Network based on Jool

#31

Post by somerandomqaguy »

tsimionescu wrote: post #9
gertrunde wrote: post #7

Not sure I entirely agree with : "Here is the classical topology of home network." ... "And all the LAN hosts have one /64 IPv6 prefix." Are people really deploying IPv6 like this? Rather than a /64 to a vlan? (Personally, in the home, I'm just using DHCPv6-PD to delegate a different /64 to each VLAN).

Who has multiple VLANs in a home network??

It's starting to get a bit more common but in a roundabout way. Telus managed Wifi routers can provides isolated guest networks, which AFAIK uses VLAN's and firewall rules internally. It's not visible to the end user though.

https://www.telus.com/en/support/article/create-a-guest-netw...

Re: IPv6-only Network based on Jool

#32

Post by rendaw »

eqvinox wrote: post #23

It should be noted in-network DNS64 is a fallback for situations where end devices don't have native support for NAT64 (either with a CLAT or with local DNS64). (Network side DNS64 breaks DNSsec) RedHat is working to get CLAT on regular Linux hosts, where it has been direly missing.

I guess this is because sometimes hosts use bare IPv4 address and don't go through DNS and thus DNS64 doesn't work for them? And if the host supports translating the addresses itself (CLAT) why use DNS64 at all?

But this is the first time I've heard of that. Do any devices support it at all? I'm still struggling with IPv6 issues on my iphone.

Re: IPv6-only Network based on Jool

#33

Post by rendaw »

I used Jool! It worked great, but with some caveats.

My ISP does DS-lite which is some abomination where the shared (split by port) IPv4 address is calculated based on the IPv6 address? Using a fixed mapping table? Which is both very popular here and has zero linux support.

They had another option to do PPPoE IPv4 + SLAAC IPv6, but for this option they didn't support DHCP prefix delegation. So I had to use this, and to work around that I needed to make my IPv6 network bridged.

The problem is Jool hooks into the linux routing table, and in the bridged network none of the outbound packets reach that table. So I had to 1. rewrite their RAs with my own DNS64 server and 2. mangle NAT64 packets to look as if they're sent to the router directly so they hit the routing table (and get processed by Jool): https://github.com/andrewbaxter/portalino/blob/main/source/o...

Then I hit random MTU issues. MTU should be auto configured (and fixed when there's issues) but I saw problems with Chrome/Firefox refusing to load pages until I tried again at least 30s later until I forced the MTU lower.

So close, but still so far.

Re: IPv6-only Network based on Jool

#34

Post by eqvinox »

rendaw wrote: post #32
eqvinox wrote: post #23

It should be noted in-network DNS64 is a fallback for situations where end devices don't have native support for NAT64 (either with a CLAT or with local DNS64). (Network side DNS64 breaks DNSsec) RedHat is working to get CLAT on regular Linux hosts, where it has been direly missing.

I guess this is because sometimes hosts use bare IPv4 address and don't go through DNS and thus DNS64 doesn't work for them? And if the host supports translating the addresses itself (CLAT) why use DNS64 at all? But this is the first time I've heard of that. Do any devices support it at all? I'm still struggling with IPv6 issues on my iphone.

Desktop Linux is to my knowledge the only "major" OS without a CLAT; Android and iOS/MacOS have had a CLAT for ages and I believe Windows got one recently*.

* not sure about that

> I guess this is because sometimes hosts use bare IPv4 address

This, and also legacy applications just not using IPv6 sockets.

Re: IPv6-only Network based on Jool

#35

Post by tsimionescu »

sgjohnson wrote: post #12
tsimionescu wrote: post #9

Earlier quoted context omitted.

Who has multiple VLANs in a home network??

I don't think an average home user even knows what a VLAN is. This, on the other hand, is Hacker News.

The question was about users in general, not HN users in particular.

Also, just because you know how to do it, doesn't mean you want to tinker with a complex network topology on your home network.

Re: IPv6-only Network based on Jool

#36

Post by ay »

eqvinox wrote: post #22
ay wrote: post #14

Earlier quoted context omitted.

If you have NAT64, DNS64 and use “IPv6-mostly” option 108 on DHCP, then CLAT will be activated on supporting devices automatically - and then you can turn the dhcpv4 off when you see no leases on it :-) By now there is a fair amount of material, eg: https://indico.cern.ch/event/1274792/contributions/5444353/a...

Nit: you still need DHCPv4 to send 108 ;) But also CLAT should turn on if a PREF64 is known and no IPv4 is available, regardless of 108.

True :) the nice thing with 108 is that it is supposed to be “seamless” - that is, you will see (by the absence of leases) that “it’s finally time” to remove it. And the legacy old devices will still continue to work till then.

Re: IPv6-only Network based on Jool

#37

Post by soupbowl »

rendaw wrote: post #33

I used Jool! It worked great, but with some caveats. My ISP does DS-lite which is some abomination where the shared (split by port) IPv4 address is calculated based on the IPv6 address? Using a fixed mapping table? Which is both very popular here and has zero linux support. They had another option to do PPPoE IPv4 + SLAAC IPv6, but for this option they didn't support DHCP prefix delegation. So I had to use this, and…

I've bumped into ds-lite alot for my Japanese friends living in Tokyo. I really don't like it to say the least.
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