[dns-operations] Too Open (Was: OpenDNS makes your Internet work better

Per Heldal heldal at eml.cc
Sat Jul 15 10:28:27 UTC 2006

Peter, despite your reputation for trolling, I couldn't let this go ;)

On Sat, 15 Jul 2006 10:53:33 +0200, "Peter Dambier"
<peter at peter-dambier.de> said:
> Brad Knowles wrote:
> > At 9:49 PM +0200 2006-07-14, Per Heldal wrote:
> > 
> >> From your angle, given the use of minimum 2 independent providers
> >> to host every zone, what do I loose if all listed nameserver (ns >= 2)
> >> use anycast?
> > 
> Half a billion costumers.

Get real! 

Show documentation to back that statement!  

One thing first: pitiful attempts at anycasting using blocks smaller
than RIR- and BCP prefix-filter-recommendations say don't count. Trying
to do anycast without the proper infrastructure won't work. 

I'd love to see documentation showing that 1/2bn users can't get
responses from a proper anycast rig, like e.g. the anycasted

> > 
> > But regardless of whether or not UltraDNS has been able to address 
> > their problems and come up with an appropriate solution, I remain 
> > convinced that because of the nature of /etc/resolv.conf and the 
> > typical limitations of the resolver only paying attention to three 
> > addresses listed in that file, OpenDNS will face insurmountable 
> > obstacles in trying to do the same.
> > 
> I guess we shall learn a lot from them. It is always good to learn
> form the errors other people do - and not doing them yourself :)

Wasn't this thread about OpenDNS and their resolver service?  If so,
what is the relevance of DNS-hosting? Has somone missed the difference
between resolvers and authoritative servers somewhere along the line? ;)


To stray further OT:

The issue with UltraDNS desribed in this thread relates to the fact that
they used multiple anycast IP's in the same address-block. You get
problems if you do that and don't control the infrastructure
interconnecting the various anycast locations. This is why the only
"first-class" anycast providers are providers with a network footprint
large enough to cover all their anycast locations. These providers are
the only ones who reliably can provide more than one anycast service
within each announced prefix. Different size network have different
properties. Certain properties come with scale, and can't be bought

  Per Heldal

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