Server's certificate does not match the url for www

So, as far as I’m aware, each subdomain for letsencrypt has to be registered separately. The problem I’m having is when I make an alias for, the URL doesn’t match the one in the cert and I get an ssl error. Is the only solution to make a separate apache config for www with a separate cert listed?

Assuming you’ve correctly added the www-domain to the certificate (with an extra -d www.domain), you can use this single certificate for both the www as the non-www domain.

It depends on your Apache (assuming Apache here, because you didn’t specify your used server software), you’ll have to configure this certificate in the www-virtualhost too. If you’ve used the ServerAlias directive for the www-domain inside the same VirtualHost section as the ServerName for the non-www domain, it should suffice to specify the cert just once in that VirtualHost…

Ok so I tried using the ssl files for (/etc/letsencrypt/live/
and navigating to I had the same problem in reverse.

Oh, I see. You have to specify both domains in one command when generating the cert. Does this only work with www or does it work on other subdomains?

It works for other subdomains, or even completely different domains. You can add up to 100 different names, I believe.

Oh cool. I don’t think that was the case when I joined the beta.