Let’s Encrypt allows subscribers to validate domain control using any one of a few different validation methods. For much of the time Let’s Encrypt has been operating, the options were “DNS-01”, “HTTP-01”, and “TLS-SNI-0…

Let’s Encrypt is removing support for domain validation with TLS-SNI-01. If you’re using Certbot and received an email titled “Action required: Let’s Encrypt certificate renewals” or are getting the error message: Clie…