According to your server / panel configuration , your ssl certificates can sometime only be managed from your Cpanel , so you will have to do the following to allow socketio to use those SSL certificates :
From SSH :
open the file /usr/local/apache/conf/httpd.conf
And find your Virtual host configuration for SSL , it start with :
<VirtualHost xxx.xxx.xxx.xxx:443> (xxx is your IP)
ServerName your.domain.com
Then find the paths of your certificates in :
SSLCertificateFile /var/cpanel/ssl/installed/certs/……
SSLCertificateKeyFile /var/cpanel/ssl/installed/keys/……
SSLCACertificateFile /var/cpanel/ssl/installed/cabundles/…….
Then enter those paths in backoffice > settings > advanced > configuration
hostname is your domaine name .
Then you will have to add your account user in the group “mail” with this command :
usermod -a -G mail “username” (replace username)
It will allow your siberian system user to read the certs .