Re: v6 vs gif

[Greg Troxel <gdt%ir.bbn.com@localhost>]

der Mouse <mouse%Rodents-Montreal.ORG@localhost> writes:

>>> # ifconfig gif0 inet6 (our v6 address) (our peer's v6 address)
>>> ifconfig: SIOCAIFADDR: Invalid argument
>> Please add a 'prefixlen 128', the default is '64' and is invalid for
>> host addresses.
>
> Oho!  That would explain it.  (Surely the default should be 128 when
> setting local-&-remote addresses on a point-to-point link?  Is there
> something (else) I'm missing here, or should I send- this -PR?)
>
> That seems to work.  At least, the command completes without
> complaining, and "ifconfig gif0" shows the addresses there.

I had the same issue, but the sixxs.net wiki had good examples.

I agree this is non-intuitive, and should certainly be documented, maybe
in gif(4).  I had the impression v6 was always /64, but p2p links seem
to have two /128s even if a whole /64 is assigned to the link.  If
standards really do say that /128 is right, gif should deal with just
addresses.