I also got this action required email and I first had to search for the server with the appropriate domains. I ve got server with Debian 8.11, Debian 9.6, both with Certbot version 0.10.2 using the http-01 challenge for the domains on these servers (checked with certbot renew --dry-run). Is this ok then, when http-01 is being used? I am confused, because in most of the community topics I can read that I have to update the certbot client to version 0.28.
Then there was another server with Ubuntu 16 LTS and Certbot version 0.26.1. Certbot shows that is was using the “TLS-SNI-01 validation” for two domains AND http-01 validation for the other domains. We decided to perform a complete system upgrade to Ubuntu 18 LTS. Now Cerbot version 0.23.0 is running on the updated server but using http-01 for all domains! This is also confusing because a system upgrade gets me a lower certbot version but http-01 validation for all domains. Now when I call ‘certbot renew --dry-run’ on the updated server certbot prints the following message:
“Attempting to parse the version 0.26.1 renewal configuration file found at /etc/letsencrypt/renewal/“a-porno-domain”.com.conf with version 0.23.0 of Certbot. This might not work.”
I wonder if there is still action required.