nanog mailing list archives

Re: DNS problems to RoadRunner - tcp vs udp


From: John Kristoff <jtk () ultradns net>
Date: Fri, 13 Jun 2008 14:05:44 -0500

On Fri, 13 Jun 2008 14:14:55 -0400
Jon Kibler <Jon.Kibler () aset com> wrote:

TCP is used for zone transfers.
If my server responded to TCP queries from anyone other than a secondary
server, I would be VERY concerned.

I wouldn't be unless it looked like a DDoS - and it might for some that
are seeing the results of a DNS-based DDoS mitigation device you or an
upstream put in for the first time.  These boxes force clients to switch
over from UDP to TCP for queries when a well formed UDP DNS attack hits.

John


Current thread: