Re: IPv6 woes - RFC

[Owen DeLong via NANOG <nanog () nanog org>]

> On Sep 6, 2021, at 3:55 PM, Matt Palmer <mpalmer () hezmatt org> wrote:
>
> On Mon, Sep 06, 2021 at 08:38:44AM +0200, Xavier Beaudouin via NANOG wrote:
> > Hello,
> >
> >
> > > I absolutely HATE testing, developing and supporting IPv4+IPv6, more
> > > than doubling my time, adding 3rd stack would actually not increase
> > > cost that much, it's the 1=>2 which is fantastically expensive. And
> > > costs are transferred to customers.
> >
> > Dual stack is doubling dev time ? Ok... this is quite strange...
>
> Nope, entirely normal and expected.  Coding for one case is very
> straightforward:
>
> Do thing
> Do other thing
> Do this as well
>
> Coding for two cases involves identifying each step which needs to be done
> differently for the two cases and coding up the things to be done
> differently:
>
> if case1:
>  Do thing this way
> elif case2:
>  Do same thing this other way
> Do other thing the same way regardless
> if case1:
>  Do this as well
> elif case2:
>  Don't do anything

Sure, but most of this can be obviated with IPV6_V6ONLY=false.

From that point on, your software doesn’t need to know or care whether the connection is IPv4 or IPv6, everything looks 
like IPv6.

Owen