DNS DoS ???

Sat Jul 30 16:33:14 UTC 2011

-----Original Message-----
From: Dobbins, Roland [mailto:rdobbins at arbor.net] 
Sent: Friday, July 29, 2011 6:40 PM
To: NANOG list
Subject: Re: DNS DoS ???

On Jul 30, 2011, at 1:51 AM, Elliot Finley wrote:

> my DNS servers were getting slow so I blocked recursive queries for all but my own network.

This should be the standard practice.  By operating an open recursor, you lend your DNS server to abuse as a contributor to DNS reflection/amplification attacks.

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And at this point he may as well just ACL in-front of the recursors to prevent the traffic from hitting the servers thus reducing load needed to reject the queries on the servers themselves.

-Drew