How do you use a Let's Encrypt certificate with the Alexa service?

Question

I created a Let's Encrypt certificate using SSLforFREE. It works great in the browser, but generates an "unknown certificate" error when used with an Alexa skill. Manually uploading the certificate to the Alexa service works, but it will not work as a "trusted" certificate.

Has anyone successfully used one of these as a "trusted" certificate with Alexa?

Answer 1

Oh, here's what you can do:

1. Download the contents of your fullchain.pem cert, from /etc/letsencrypt/live/<domain>/fullchain.pem on your server
2. On your skill config page, select the "SSL" Tab.
3. Mark "I will upload a self-signed certificate in X.509 format."
4. Paste the contents of your fullchain.pem file.

It worked for me. Not sure if chain or cert would be enough.

Answer 2

Dont use sslforfree. Use Letsencrypt fullchain certificates directly

Though certificates from https://www.sslforfree.com/ utilizes letsencrypt certificate chain, amazon finds an issue while tracing to a trusted certificate authority.

This is another discussion on missing certificate chains.

The solution that will work is, Use LetsEncrypt certificates directly with chained certificates to a trusted CA certificate.

For this, use certbot in order to generate LetsEncrypt certificate on your Server and follow the steps in @aldrinleal answer.