certbot-auto renew --standalone --dry-run completes without any errors. All of the certificates have been renewed recently, so none to be renewed.
Does the above running without errors, even when renewals are not required, indicate that my server has the required verification setup correctly? I have both ports 443, 80 closed in the router to the server processor where the script is running. I do not have any special dns txt records related to letsencrypt I know of.
So how is the above verification working?