Let's Encrypt gives a "can't find host" error when
Inside Virtualmin Configuration, down at the SSL section, I turned on
Request Let's Encrypt certificate at domain creation time?
On my server it fails to work. because until the apache/bind restarts happen the site isn't publicly available, so at that point in the creation of a new domain, there is no "www.whatever.com" to look at.
Immediately after the setup is complete, you can easily use the let's encrypt option in server settings, but figured you might want it to work as in the configuration options