DHCPv6-PD – First Steps • Hacker News Board

DHCPv6-PD – First Steps

#1

Post by todsacerdoti » Wed, Jun 05, 2024, 10:07 PM UTC

Re: DHCPv6-PD – First Steps

#2

Post by candiddevmike » Wed, Jun 05, 2024, 11:22 PM UTC

While the article is focused on OpenBSD, implementing DHCPv6 with systemd-networkd is really slick and typically a 1-2 line config for your interfaces:

Upstream:

  [DHCPv6]
  PrefixDelegationHint=::/56

Downstream:

  [DHCPv6PrefixDelegation]
  Token=::1

Re: DHCPv6-PD – First Steps

#3

Post by Havoc » Thu, Jun 06, 2024, 12:01 AM UTC

Curious why the FRITZ!Box is necessary? I know they popular in Germany but isn’t it like just a router OS?

Re: DHCPv6-PD – First Steps

#4

Post by tssva » Thu, Jun 06, 2024, 12:13 AM UTC

candiddevmike wrote: post #2

While the article is focused on OpenBSD, implementing DHCPv6 with systemd-networkd is really slick and typically a 1-2 line config for your interfaces: Upstream: [DHCPv6] PrefixDelegationHint=::/56 Downstream: [DHCPv6PrefixDelegation] Token=::1

I have never been able to get DHCPv6PD working with systemd-networkd on my Verizon Fios connection at home. I have using other software.

Re: DHCPv6-PD – First Steps

#5

Post by miller_joe » Thu, Jun 06, 2024, 12:20 AM UTC

This is great! I’ve been using ipv6 on openbsd for a while now, starting with a hurricane electric tunnel years ago then to native v6 on Comcast and now Sonic. Configuring ipv6 PD has not been supported in base this whole time. I recall using wide-dhcp6c years ago and then switching to the dhcpcd in the article. The situation has improved, slowly, but it will be great to have this in the base system

*EDIT*: dhcp6leased landed in base yesterday: https://www.undeadly.org/cgi?action=article;sid=202406040850...

Re: DHCPv6-PD – First Steps

#6

Post by bastard_op » Thu, Jun 06, 2024, 12:38 AM UTC

"3 Because of android refusing to implement it."

So, some interesting history for the not-network-engineers out there on ipv6 fun. https://issuetracker.google.com/issues/36949085

Why do people hate ipv6? Google comes to mind as one place to start.

Re: DHCPv6-PD – First Steps

#7

Post by j16sdiz » Thu, Jun 06, 2024, 12:51 AM UTC

bastard_op wrote: post #6

"3 Because of android refusing to implement it." So, some interesting history for the not-network-engineers out there on ipv6 fun. https://issuetracker.google.com/issues/36949085 Why do people hate ipv6? Google comes to mind as one place to start.

No.

In IPv6, you can get an address using RA. DHCPv6 only if you want to smuggle some unrelated metadata as options (which, of course, not widely used outside enterprise). DHCPv6-PD are used only when you need a whole prefix.

If everybody implement all the specs out there, we will have two different DNS record type, 4 or 5 address allocation schemes, a handful of IPv6-over-IPv4 protocol, whole a lots of incomplete and incompatible IPv4-ovr-IPv6 protocol.... Etc... while telling everybody ipv6 is simple and ask why we haven't got there yet

Re: DHCPv6-PD – First Steps

#8

Post by j16sdiz » Thu, Jun 06, 2024, 1:03 AM UTC

j16sdiz wrote: post #7

bastard_op wrote: post #6

"3 Because of android refusing to implement it." So, some interesting history for the not-network-engineers out there on ipv6 fun. https://issuetracker.google.com/issues/36949085 Why do people hate ipv6? Google comes to mind as one place to start.

No. In IPv6, you can get an address using RA. DHCPv6 only if you want to smuggle some unrelated metadata as options (which, of course, not widely used outside enterprise). DHCPv6-PD are used only when you need a whole prefix. If everybody implement all the specs out there, we will have two different DNS record type, 4 or 5 address allocation schemes, a handful of IPv6-over-IPv4 protocol, whole a lots of incomplete an…

I meant.... I love DHCPv6.

If only RA wasn't mandatory part of IPv6, I am all for DHCPv6.

It's the fault of early IPv6 designers with NIH syndrome created this mess.

Re: DHCPv6-PD – First Steps

#9

Post by wmf » Thu, Jun 06, 2024, 1:07 AM UTC

bastard_op wrote: post #6

"3 Because of android refusing to implement it." So, some interesting history for the not-network-engineers out there on ipv6 fun. https://issuetracker.google.com/issues/36949085 Why do people hate ipv6? Google comes to mind as one place to start.

Google doesn't hate IPv6; they've put huge effort into it. This particular issue is just weird.

Re: DHCPv6-PD – First Steps

#10

Post by kiwijamo » Thu, Jun 06, 2024, 1:32 AM UTC

j16sdiz wrote: post #8

j16sdiz wrote: post #7

Earlier quoted context omitted.

No. In IPv6, you can get an address using RA. DHCPv6 only if you want to smuggle some unrelated metadata as options (which, of course, not widely used outside enterprise). DHCPv6-PD are used only when you need a whole prefix. If everybody implement all the specs out there, we will have two different DNS record type, 4 or 5 address allocation schemes, a handful of IPv6-over-IPv4 protocol, whole a lots of incomplete an…

I meant.... I love DHCPv6. If only RA wasn't mandatory part of IPv6, I am all for DHCPv6. It's the fault of early IPv6 designers with NIH syndrome created this mess.

Out of interest as I have found IPv6 RA to work flawlessly for my home network (alongside legacy IPv4 DHCP), what advantage (if any) is there in deploying DHCPv6 within the home LAN? Or were you meaning to say DHCPv6 is great for certain (enterprise?) use cases?