Let’s Encrypt IPv6-only
One of the much requested features for Let’s Encrypt free SSL certificates is support for IPv6-only hosts. Whilst this is promised in the very near future we’re happy to say that IPv6-only hosts behind our NAT64 & Proxy services work out of the box with Let’s Encrypt.
To test it we took the traditional dogfood approach, this website is run on an IPv6-only VM and we’ve just enabled Lets Enrypt SSL support on our own blog. As soon as Let’s Encrypt offer SSL certificates for IPV6-only hosts with no proxy and no NAT64 we’ll give that a try too.
DNS-based domain validation (dns-01)
An alternative approach would be to use dns-01 validation using our DNS API. Our API speaks native v6, so that should work just fine on a truly single-stack IPv6 host.