Lets Encrypt failed, Error looking up A and AAAA records.

Posted May 15, 2019 15.8k views
ApacheDigitalOceanNetworkingLet's EncryptUbuntu 18.04

I have been experiencing challenges using certbot to issue an ssl cert to a sub-domain mapped to one of my droplets. I have an ssl cert issued to the main domain and two other sub-domains and i had no problem doing that. However of recent when i try to issue an ssl cert to this particular sub-domain i get the following errors


  • The following errors were reported by the server:

Type: connection
Detail: dns :: DNS problem: SERVFAIL looking up A for

Type: connection
Detail: dns :: DNS problem: SERVFAIL looking up A for

To fix these errors, please make sure that your domain name was
entered correctly and the DNS A/AAAA record(s) for that domain
contain(s) the right IP address. Additionally, please check that
your computer has a publicly routable IP address and that no
firewalls are preventing the server from communicating with the
client. If you’re using the webroot plugin, you should also verify
that you are serving files from the webroot path you provided.

In the process of debugging i have tried using [](http://) to lookup the sub-domain and it fails to provide any record even for the main domain that already has an existing ssl cert. My question is, is it normal for to not be able to find any record from your domain. If not what could be causing this ?

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1 answer

Hey there,

I’ve checked the records on the subdomain listed, it returns a correct A record pointing to DO:

Further, I ran http & dns debug tests for that subdomain through Let’s Debug ( and they both came back fine.

Are you still encountering the issue? It might be worth asking on the LE community forums as they might be more in-tune with handling such issues :)