RE: v6 & DSL / Cable modems

["TJ" <trejrco () gmail com>]

> What most people do of course is VRRP.

Sure, or HSRP or GLBP ... all still doable.


> Barring that, you just specify multiple default routers, and the client
will
> select the router that still responds to ARP.  But support for this is not
> universal, so.

Indeed, not universal and in fact default behaviors vary wildly.


> When that isn't available, what I have done in the past here is to use the
> DHCP server to give out a default router option that is sorted according to
> the DHCP relay agent that was used to reach the server (keyed on giaddr
> contents).
>
> The net result is that the client uses the default gateway which it used to
> reach the DHCP server, and so will automatically receive an updated value
if
> that router fails, as part of DHCP lease rebinding (it will reach the
server
> via the alternate router).

Which I think is pretty slick.
OOC - between the "router fails" and "I renew/rebind my address", is the
host down and out?
        So you are accepting either a noticeable outage or tweaking your
lease times, yes?