title: Letsencrypt add domain to existing certificate
body: <p>I am just simply trying to add the domain <code>test.example.com</code> to the certificate that already exists for <code>example.com</code>. How do I add a domain to my existing certificate and replace the old certificate?</p>
  
  <p>I have tried these few commands</p>
  
  <pre><code>./letsencrypt-auto certonly --cert-path /etc/letsencrypt/archive/example.com --expand -d test.example.com
  
  ./letsencrypt-auto certonly -d example.com --expand -d test.example.com
  </code></pre>
  
  <p>Result: both created a brand new cert in a new folder test.example.com-0001</p>
  
  <pre><code>./letsencrypt-auto certonly --renew-by-default  --expand -d test.example.com
  </code></pre>
  
  <p>Result: error folder test.example.com already exists.</p>
  
  <pre><code>./letsencrypt-auto renew --expand -d orange.fidka.com
  </code></pre>
  
  <p>Result: error, I can only renew if my certificate is expired.</p>