On 3/27/2013 8:47 AM, William Herrin wrote:
On Tue, Mar 26, 2013 at 10:07 PM, Tom Paseka <tom@cloudflare.com> wrote:
Authoritative DNS servers need to implement rate limiting. (a client shouldn't query you twice for the same thing within its TTL). Right now that's a complaint for the mainstream software authors, not for the system operators. When the version of Bind in Debian Stable implements this feature, I'll surely turn it on.
Tracking the clients would be a huge dataset and be especially complicated in clusters. They'd be better off at detecting actual attack vectors rather than rate limiting. However, there are enough nodes out there to easily spread a trickle to avoid individual detections. You don't want to DOS your amplifier, after all. It also wouldn't be hard to rotate through different requests to defeat the "rate limits". Jack