I’m trying to put Lets Encrypt on my Ubuntu 18.04 server with the Ralph application installed (https://ralph-ng.readthedocs.io/en/latest/installation/installation/)
In the file /etc/nginx/sites-available/default I put:
server_name cmdb.mydomain. com;
I use the command:
sudo certbot certonly -d cmdb.mydomain.com
But it gives me the following error:
Failed authorization procedure. cmdb.mydomain. com (http-01): urn:ietf:params:acme:error:dns :: DNS problem: NXDOMAIN looking up A for cmdb.mydomain. com
I have also tried it by adding www.cmdb.mydomain. com and the result is the same.