Eliminating IPv6 (?)

[Viktor Dukhovni]

On Tue, Jun 18, 2019 at 01:09:16AM -0700, christian russell wrote:

> > I ask again, is this really such an unreasonable thing to hope for?
> 
> If I were allocating work-hours on FreeBSD development my answer would be:  “yup"  ¯\_(ツ)_/¯

Agreed.  I find it takes very little effort to not have IPv6 get
in my way, and with that taken care of, it is then occasionally
even useful.  If this thread boils down to annoyance about localhost
resolving to both "::1" and "127.0.0.1" then use "127.0.0.1" instead
of "localhost" in any configuration files where that's what you
mean.

Though the draft has been dormant for a while, at some point
"localhost" may indeed simply be hardwired into libraries,
rather than delegated to name resolution mechanisms:

    https://tools.ietf.org/html/draft-ietf-dnsop-let-localhost-be-localhost-02

The unbound resolver has a default "localhost" zone:

            localhost
                 The IP4 and IP6 localhost information is given. NS and SOA
                 records are provided for completeness and to satisfy some DNS
                 update tools. Default content:
                 local-zone: "localhost." redirect
                 local-data: "localhost. 10800 IN NS localhost."
                 local-data: "localhost. 10800 IN
                     SOA localhost. nobody.invalid. 1 3600 1200 604800 10800"
                 local-data: "localhost. 10800 IN A 127.0.0.1"
                 local-data: "localhost. 10800 IN AAAA ::1"

With just the "IPv4" address for "localhost" in /etc/hosts,
getaddrinfo() performs the AAAA lookup via DNS!  But likely with a
default domain appended.  Therefore, additional local-data may be
needed for "localhost.example.org." to authoritatively deny the
existence of the IPv6 address.

But all of that is much work for little gain.  Far simpler to just
make "::1" work, and/or use "127.0.0.1" instead of localhost as
needed.

-- 
	Viktor.