Subject: Re: Peculiar ICMP6 redirect rejection
To: None <tech-net@netbsd.org>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-net
Date: 08/19/2002 18:46:44
>> but why does ND want to install such a route to begin with?  R has
>> no business doing ND for L at all, since L isn't on the /112 R's on.
> You're thinking in IPv4 paradigms.   IPv6 [...] has the ability to
> directly inform a node that some other node with what looks to be an
> off-link address, is actually on-link and can be reached directly.

Aha!  Thank you.  This looks like a bug in the code for that, then, in
that it isn't replacing the existing host route with the LL route.

>> (those not interested in watching kre and me chatter at one another
>> can stop reading now :-)
> That is probably everyone, and after this message, I think me
> included...

Well, you may not see this, then, but in case you do, thank you for
taking the time to explain things to me.  Eventually I'll get all this
stuff down....

>> Because until the DNS infrastructure supports it well, renumbering
>> isn't going to become something that's undertaken casually.
> Sure, but what is required to make renumbering work wasn't part of
> the original discussion.

No.  I was offering that as a reason I wasn't concerned about
renumbering breaking my route-to-global-address setup.

> (that is, no "renumbering without DNS support is hard, so because of
> that I won't care if I also make it hard by using globals for
> routes")

More like "it's so hard - witness DNS lack of support - that in
practice it's going to happen seldom enough that it's not worth
worrying about".

>> As for nonstandard netmasks, I'm not sure what's "nonstandard" about
>> any of the netmasks I'm using,
> The conventional IPv6 wisdom in some quarters is that all links are
> required to use a /64 (nothing bigger, nothing smaller).

Eh.  Well, see my response to William Waites if you want my opinion of
that.  (Most briefly, I agree with the side you seem to.)

> I doubt the netmask is related to any of the questions here.

Me too.  I may try switching everything to /64s (it's cramped, but
it'll fit), and if, as I fully expect, it still misbehaves, maybe
itojun will then admit there's something wrong.

> Using multiple prefixes on a link, without advertising them as being
> on link may be stressing the implementation, but it certainly isn't
> non-standard.

Advertising them?  Who should (for whatever value of "should") be
advertising them, to whom, and how?  I think there's another piece of
v6 I don't know lurking here....

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