themiron at mail.ru
Mon Oct 14 12:03:23 BST 2013
> The problem with that is that RDNSS and DNSSL are per interface, not per-
> prefix. Maybe the calculation should the maximum valid time of any prefix
> advertised on the interface?
It will not work for several different prefixes and serveral different
global-scope addresses on dnsmasq interface.
Since it's per interface (actually not, per router, but whatever), and
onlink flag is always set, auto-cooked [::] rdnss address should contain
link-local address of that interface, not global. After that, lifetimes can
be max (or 2/3 of max to fit RFC defaults) of any valid ra lifetime.
Also, announcing link-local addres of interface as RDNSS make life easier
while prefix changing, renumbering, etc.
As for user-specified RDNSS addresses, it's up to him to shoot in own foots
and specify static or dynamic servers.
Best Regards, Vladislav Grishenko
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