Templin, Fred L wrote:
The presence of default routes means that the host should
accept packets from all four routers equally, i.e., and not
only accept the ones from R1 and R2 while dropping those
from R3 and R4, right?
What do you mean by "accept"? The content of the default router list (or
a routing table in general) doesn't have any impact on what received
packets are accepted by a host.
Here the admin wants packets to P1 to only go via R1 or R2.
However, should there be some short-term flakyness for the connectivity
between the host and R1 and R2 (just some wireless packet drops over a
40 second period is sufficient), then NUD could decide that R1 and R2
are unreachable.
But if R1 and R2 are both truly unreachable, shouldn't
the host be allowed to fail over to R3 and R4, which are
legitimate forwarders of packets that the host accepts?
They would do that after the more specific routes pointing at R1 and R2
times out. But doing it just because 3 NUD packets were lost makes
things less predictable.
If you, instead of using RFC 4191 to do more specific routes, run ripng
on the host you'd see the expected behavior that the route remains in
use until it times out; NUD might at most affect the selection when
there are Equal Cost Multipath routes.
Erik
--------------------------------------------------------------------
IETF IPv6 working group mailing list
[email protected]
Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6
--------------------------------------------------------------------
