[DNSOP] drop udp to stop DDOS?

"A. Schulze" <sca@andreasschulze.de> Sat, 01 October 2016 15:36 UTC

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Date: Sat, 01 Oct 2016 17:36:27 +0200
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From: "A. Schulze" <sca@andreasschulze.de>
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Subject: [DNSOP] drop udp to stop DDOS?
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Hello,

a nsd user posted an interesting question:
https://open.nlnetlabs.nl/pipermail/nsd-users/2016-September/002364.html

> Could we eliminate the DDoS threat by just turning off UDP?
>
> Recursive servers I understand probably have to keep accepting them,  
> but authoritative servers are only intended for recursive servers to  
> query, so would it be safe to just drop port 53 UDP requests?

are there any experiences/opinions on that?
Andreas