Eliminating IPv6 (?)

[Eugene Grosbein]

18.06.2019 14:44, Ronald F. Guilmette wrote:

>>> How can I turn off IPv6 entirely without rebuilding the kernel?
>> You cannot. GENERIC kernel specifically enables IPv6 support and you need to
>> disable it at compile time.
>> And if you do, you better rebuild the world too using WITHOUT_INET6=yes in the
>> /etc/src.conf
>> or else some utilities compiled with INET6 by default will query kernel
>> for IPv6-specific data (like routing entries) and complain that your kernel does 
>> not know about it.
>>
>> World built WITHOUT_INET6 has no such rough edges.
> 
> OK, so I obviously expressed myself badly.  Let me try again.
> 
> IPv6 support is enabled in a the stock kernel.  OK.  Fine.  But just because
> that feature is present in the kernel, that does not imply that anything in
> userland -has- to actually make any use of it at all.
> 
> *Something* is doing ifconfig on my loopback (lo0) interface.  What is that
> thing and how can I get it to stop doing that?

It is not userland. It is a kernel itself.

IPv6 standards are very different comparing to IPv4. They mandate some level of actual usage of IPv6.
Easiest (and sometimes only) way to get rid of this is to rebuilt the kernel.