Google Captcha on web searches

Chris Murray chris at
Tue Nov 10 22:43:04 UTC 2015

Hi Nikolay,

The "popular open dns services" you refer to appear to be Proxy/VPN
services that also provide DNS to get around region blocking. These
services proxy and/or NAT users behind a single IP address to make it
look like you are coming from a different country.

I may be biased, but when I think of popular open DNS services I think
of OpenDNS or Google DNS, and you should *never* see a captcha as a
result of using OpenDNS. Disclaimer: I work for OpenDNS, and while I
can't speak to Google DNS, I have never heard of this behaviour with
their service either.

Just wanted to clarify.
- Chris

On Tue, Nov 10, 2015 at 12:29 PM, Nikolay Shopik <shopik at> wrote:
> When I've started using DNS from unotelly service, captcha starts
> appears from time to time. If I change DNS to something else, catcha
> gone immediately.
> Its probably related to DNS geo-locating to decide what records serve to
> client
> On 10/11/2015 23:00, Christopher Morrow wrote:
>> On Tue, Nov 10, 2015 at 1:09 PM, Nikolay Shopik <shopik at> wrote:
>>> You may get captcha if you are using popular open dns services. At least
>>> this is what I've seen.
>> pardon, what?
>>> On 10/11/2015 20:28, Joseph Jenkins wrote:
>>>> We started getting a Google Captcha for our web searches this morning. Does anyone have contact info for Google so that I can contact them and figure out where the traffic is coming from on my side or what service it is going to so that I can track down the users?
>>>> Thanks,
>>>> Joe Jenkins
>>>> 909.636.2097

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