Subdomain produces SSL_ERROR_NO_CYPHER_OVERLAP error

Hey,

That error usually points to the SSL certificate not matching the www subdomain. From your description it sounds like mysite.com is covered but www.mysite.com is not, even though you pointed www to @ with a CNAME.

Can you confirm how you’re serving the site? Are you running Nginx on a Droplet with Certbot handling the certificates, or are you using App Platform / a Load Balancer?

If it’s Nginx + Certbot, make sure that:

• Your certificate request includes both mysite.com and www.mysite.com (for example with certbot --nginx -d mysite.com -d www.mysite.com).

• Your Nginx server block has server_name mysite.com www.mysite.com; so both domains are covered.

If you’re on App Platform or a DO Load Balancer, you’d just need to add www.mysite.com as a custom domain so Let’s Encrypt can provision a cert for it.