Google Captcha on web searches

Nikolay Shopik shopik at
Tue Nov 10 23:09:24 UTC 2015

Hi Chris,

Yeah I probably should worded that differently not 'open dns services',
sorry about that. In my case there is no proxy/vpn service (i know they
can do that), just DNS changes. For some reason that cause
false-positive detection in google from time to time.

On 11/11/2015 01:43, Chris Murray wrote:
> 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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