Subject: Re: Peculiar ICMP6 redirect rejection
To: der Mouse <mouse@Rodents.Montreal.QC.CA>
From: William Waites <ww@styx.org>
List: tech-net
Date: 08/19/2002 13:10:01
>>>>> "derMouse" == der Mouse <mouse@Rodents.Montreal.QC.CA> writes:
derMouse> ICMP6 redirect rejected; not equal to
derMouse> gw-for-src=fe80:0001::02a0:24ff:fe66:fb23 (must be
derMouse> same): (src=fe80:0001::0210:5aff:fefc:5c1a
derMouse> dst=2001:0700:0400:0150::0001:0001
derMouse> tgt=fe80:0001::02a0:24ff:fe66:fb23)
derMouse> The address in the gw-for-src and tgt= fields is the LL
derMouse> address of the "portable" machine. The src= address is
derMouse> the LL address of the gateway to the rest of the world
derMouse> and the dst= address is the address I'm trying to make
derMouse> portable. (1 is the correct scope ID on that machine.)
That looks prima facie like a bug -- why is this redirect being
rejected? The only non LL address is the one that is not on the local
subnet so who cares about the mask at that point, standard or not?
Unless the neighbour is trying to use its LL address as the source IP
for its packets or some such... Maybe a tcpdump would give a better
idea of what's actually going on...
>> Standard subnet size is /64. Wasteful of bits? Maybe.
derMouse> Very. It means that at one stroke, whatever genius
derMouse> decided on that has just negated much of the benefit of
derMouse> IPv6
I tend to agree but...
-w