On Jun 28, 2021, at 10:26 PM, Cameron Steel <tugzrida@gmail.com> wrote:

To some extent, yes.

In the JSON results download, the dst_addr key will provide the address that the probe sent its query to, however this will probably not be massively useful, as it’ll often be the address of a local router or other DNS cache.

Finding out what resolver a given client is using at the level of "is this Cloudflare/Google/Local ISP/etc" is a little harder and requires using either an NSID query, which you can set on Atlas measurements but may not be supported by all resolvers, or a "whoami" style service like Akamai’s: https://developer.akamai.com/blog/2018/05/10/introducing-new-whoami-tool-dns-resolver-information.

Hope that helps

Cameron

On 29 Jun 2021, at 11:12, pravicha <pravicha@masonlive.gmu.edu> wrote:

Hello,

I’ve been trying to get dns measurements for a couple of domains over different regions using atlas probes. Is there a way to find the resolver’s IP used by the probes when use_probe_resolver is set to true?

Thanks