I am starting a small SaaS company that uses a check for DNS record before creating service. Letsencrypt cert happens during service creation. It would be best to ensure that if our check succeeds, letsencrypt will succeed in finding this domain record as well. This should be easily solvable if lets…

Google DNS Servers are used. You can check manually here: https://dns.google.com/ You can also specify the server to use with dig http://droptips.com/using-dig-to-query-a-specific-dns-server-name-server-directly-linux-bsd-osx Andrei

Google’s DNS is evil, not using that for my servers, but I will have it coded on our site to dig for it. Thanks for the reply.

I kept seeing this in relation to the DNS challenge, not http. Will wait for other parties to clarify.

I agree with @danb35 ’s answer: Let’s Encrypt doesn’t use anyone else’s recursive resolver but goes right to the source (making its own queries to the authoritative nameservers for the particular domain in question).

makes sense - apologies for confusing people @schoen if there are multuple name servers are all checked by LetsEncrypt or does is it just the first name server?

Would love to get verification as to what DNS server it connects to in order to verify the TXT record. I am getting this error: Failed authorization procedure. 45woodburn.faure.ca (dns-01): urn:acme:error:connection :: The server could not connect to the client to verify the domain :: DNS problem…

[image] paulfaure: Would love to get verification as to what DNS server it connects to in order to verify the TXT record. It sends a query to one of your authoritative DNS servers, choosing in some typical DNS way; i don't know which one. (Arbitrary, randomly, or possibly something influenced…

[image] mnordhoff: It sends a query to one of your authoritative DNS servers, choosing in some typical DNS way; i don't know which one. (Arbitrary, randomly, or possibly something influenced by latency or reliability.) One is picked randomly from the set of authoritative servers. Edit: update…

Is there any technical foundation for this assertion about Google DNS?

Yes, there is. Google gets to see your queries in plaintext. That’s it.

DNS Servers used by LetsEncrypt for Challenges

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danb35 April 15, 2017, 10:38pm 4

Are you sure? I thought Let's Encrypt always queried the authoritative servers for the domain in question.

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DNS Servers used by LetsEncrypt for Challenges

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