Google Public DNS Problems?
jabley at hopcount.ca
Thu May 2 16:10:40 UTC 2013
On 2013-05-02, at 11:59, Charles Gucker <cgucker at onesc.net> wrote:
> That's not entirely true. You can easily do lookup for
> whoami.akamai.net and it will return the unicast address for the node
> in question (provided the local resolver is able to do the
> resolution). This is a frequent lookup that I do when I don't know
> what actual anycast node I'm using.
Using 188.8.131.52 to tell me about whoami.akamai.net tells me what Akamai authoritative server Google last used to answer that query.
If I can rely upon there being an Akamai auth server every place there's a Google 184.108.40.206 server, then that does seem fun and useful for identifying the Google node I'm using. Is that the case?
(If I ask 220.127.116.11, which is somewhere 30ms from Toronto, about identity.l.root-servers.org/IN/TXT then the answer I get just now is "Paris, France". L-Root and Google/18.104.22.168 are not colocated. So the usefulness of this technique in general to identify Google nodes depends on deployment assumptions.)
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