Re: New Office, New Network. Questions.

[Owen DeLong <owen () delong com>]

To provide some additional clarity and detail:

1.      No, you can’t to the best of my knowledge hand out any IPv6
        parameters via IPv4, nor should you really want to.

2.      You can hand out IPv6 DNS resolver information from either or both
        of SLAAC and DHCPv6.

        For SLAAC, you’ll need routers that support RFC 6106. Juniper finally
        added this in 14.1.

        Cisco added it in 15.4(1)T, 15.3(2)S

        More information here: https://en.wikipedia.org/wiki/Comparison_of_IPv6_support_in_operating_systems

        To the best of my knowledge, DNS is a configuration option in all DHCPv6
        implementations.

3.      I disagree with Baldur about not bothering with IPv6 DNS resolvers.
        Given that the long term goal is to get back to single-stack networking,
        but with the single stack being IPv6, each and every vestigial IPv4
        dependency you leave lying around is just another thing you need to clean
        up at some point in the future. Since it’s so completely easy to enable
        dual-stack (or even better IPv6-only) resolving when you first deploy
        IPv6 to your end-systems, why not just do that?

Owen

> On Jul 13, 2016, at 15:53 , Baldur Norddahl <baldur.norddahl () gmail com> wrote:
>
> "Is there a reason you use DHCPv6 and SLAAC? Is it for compatibility? Can I
> use the DHCPv4 to give out DNSv6 addresses?"
>
> Unless you plan om having IPv6 only hosts, there is no advantage in
> providing IPv6 DNS servers. Just stay with IPv4 for your DNS resolver in
> the DHCPv4 config. Notice that your IPv4 DNs resolver is perfectly capable
> of providing AAAA IPv6 replies.
>
> Using DHCPv6 in a corporate environment makes it easier to track which
> machine has an IP address as you can lookup the info in the DHCP lease
> database. Also some prefers the nice short addresses that you get from DHCP
> compared to SLAAC.
>
> My network has both enabled, so my tablet has the following two addresses:
>
> SLAAC: 2a00:7660:5c6:0:74cd:d48c:8230:a44f
> DHCP: 2a00:7660:5c6::701
>
> The later is easier to type if you have to add rules to your firewall etc.
>
> Regards
>
> Baldur