Compte-tenu du danger de ces résolveurs ouverts, dénoncé depuis
longtemps
<http://www.bortzmeyer.org/fermer-les-recursifs-ouverts.html>
<http://www.rfc-editor.org/rfc/rfc5358.txt>, et récemment illustré par
l'attaque contre Spamhaus/Cloudflare, ce travail est l'occasion de se
livre à une chasse aux résolveurs DNS ouverts sur votre
réseau. Indiquez votre numéro d'AS à l'auteur et il vous indiquera les
adresses dangereuses chez vous.

---------------------------
Liste de diffusion du FRnOG
http://www.frnog.org/
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I've continued to update my dataset originally posted about two weeks ago.  
Please take a moment and review your CIDRs which may be running an open 
resolver.

I've exposed one additional bit in the user-interface that may be helpful.  
Some DNS servers will respond with RCODE=0 (OK) but not provide recursion.  
nearly 90% of the servers in the database provide recursion.

Some raw stats are also available via the 'breakdown' link on the main site.

If you operate a DNS server, or have an internal group that does, please take a 
moment and review your networks.

If you email me in private from a corporate address for your ASN, I can give 
you access to a per-ASN report.

Due to a change in methodology, I have increased the number of servers observed 
from 27.2 million to 30.2 million hosts.

2013-04-07 results

30269218 servers responded to our udp/53 probe
731040 servers responded from a different IP than probed
25298074 gave the 'correct' answer to my A? for the DNS name queried.
13840790 responded from a source port other than udp/53
27145699 responses had recursion-available bit set.
2761869 returned REFUSED

In addition, please do continue to deploy BCP-38 to prevent spoofing wherever 
possible.  I know at $dayjob we have been auditing this and increased the 
number of customer interfaces that can not spoof.

- Jared

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