
Looking for the file of configuration:
sudo ps aux | grep nginx
root 1595 0.0 0.1 33204 3196 ? Ss 10:05 0:00 nginx: master process /usr/sbin/nginx -c /var/lib/zentyal/conf/nginx.conf
# ...
The content of the file is:
...
server {
listen 8443;
ssl on;
ssl_certificate /var/lib/zentyal/conf/ssl/ssl.pem;
ssl_certificate_key /var/lib/zentyal/conf/ssl/ssl.pem;
ssl_session_timeout 5m;
ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
ssl_ciphers "ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:!aNULL:!eNULL:!EXPORT:!DES:!RC4:!3DES:!MD5:!PSK";
ssl_prefer_server_ciphers on;
access_log /var/log/zentyal/access.log;
root /usr/share/zentyal/www;
...
But remember you have to do the customizations in the respective stubRead this:
https://doc.zentyal.org/en/appendix-c.html#stubsCheers!