Schrodinger wrote: > What I am confused about is that without ACCEPT_RTADV on re0, FreeBSD > doesn't perform Neighbour Solicitation for the default gateway but with > ACCEPT_RTADV it does ..... Why ? This is Neighbour Solicitation and not > Router Solicitation.... > > I understand that FreeBSD doesn't consider the defaulte gateway to be > "on-link" so it does not perform ND for it but why does it perform ND > when ACCEPT_RTADV is set on re0 ? "Surely" ACCEPT_RTADV only affects > Router Advertisements / Solicitations and not ND. > > I have done packet captures and with ACCEPT_RTADV I see the initial > Neighbour Solicitation and the Neighbour Advertisement to and from my > default gateway. > > Without ACCEPT_RTADV - FreeBSD simply doesn't try to perform ND for the > address. This is where I am uncertain if this is expected or not.
That is a good question and I'd be interested in an answer too. Perhaps FreeBSD is implementing a predecessor to RFC 4861, i.e. the now obsolete RFC 2461: RFC 4861, Appendix F: Changes from RFC 2461 o Removed the on-link assumption in Section 5.2 based on RFC 4943, "IPv6 Neighbor Discovery On-Link Assumption Considered Harmful". RFC 4943, Abstract This document describes the historical and background information behind the removal of the "on-link assumption" from the conceptual host sending algorithm defined in Neighbor Discovery for IP Version 6 (IPv6). According to the algorithm as originally described, when a host's default router list is empty, the host assumes that all destinations are on-link. Mark _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
