[dns-operations] TTL=0; Last known good answer (Re: dns retries amplify attack)

[Jared Mauch]

This was my thought. This is really an unreachable authority issue. Would also help sites that become disconnected from the internet due to outage or other work. 

Jared Mauch

> On Oct 25, 2016, at 3:26 AM, Dave Warren <davew at hireahit.com> wrote:
> 
> I wonder if these concerns could be negated by only applying the "use
> stale data" logic when all authoritative servers timeout (or maybe also
> a SERVFAIL?), but a REFUSED, NOERROR, NXDOMAIN would still be handled
> with current logic?
>