I've used Letsencrypt to generate my self-signed ssl certs but when I was trying to access my sites at browser I was receiving an error: ERR_SSL_OBSOLETE_VERSION Researching I found the problem, now the browsers were not supporting anymore the TLSv1/TLSv1.1/SSLv3, so we should update our sites (in my case, /etc/nginx/sites-available) with: ssl_protocols TLSv1.2 TLSv1.3; After that you should just restart the NGINX service and the sites start to be accessible again.