I am putting my mind into this writing here wihich the extension from the earlier thread in here, so bear with me. # First Part Basically as stated, I am trying to add support for Let's Encrypt validation via DNS but I couldn't think of a better solution other than adding an extra tab (LE) in web settings (Sites > Websites > Create / Edit Website) for Let's Encrypt (right after SSL tab). My idea is, within this tab, there should be several info that must be selected and / or added in order to use DNS feature. The first option will be to choose to leave it as it is (i.e. the default webwoot method), so the current way of creating LE SSL certs (via valid website) will be implemented; however, if DNS method is selected instead, then certbot (as default LE client) will attempt to request the certs via DNS validation. At this stage I am attempting with certbot only so other other LE client / script like Neilpang acme.sh will have to wait. Then there should be a list of DNS server type to be selected from the official certbot plugins currently available; where from here, a detail for the website DNS config file (the credentials file) should be provided to correspond the respective selected DNS server. Of course, ideallly for own ISPConfig DNS server (a multi-server case), no information is needed as it should be done automatically via its DNS server internal function (to be created as well); but this will also have to wait since I don't have a proper ISPConfig DNS server to test. The information provided will be added to /etc/letsencrypt/.secrets/domain.tld and this /etc/letsencrypt/.secrets folder will be chmod to 600 (refer to this post) for security that will be called upon the certs creation or renewal. So for this part, I think web_vhost_domain_edit.php will be the most relevant (as well as its template and language files, of course). # Second Part For this part I believe that only letsencrypt.inc.php that needed to be modified so that it will by default choose webroot - current way of creating LE SSL certs (via valid website), but when DNS is selected, the credentials file as created earlier will be used in order to request and validate the website via DNS. Please advise me if there is some other files that need to be looked into to make this work, so I can try to work it out properly. Thank you.