When you install SolusVM it generates a self signed SSL certificate for use with the end user control panel and admin interface, however it would be wise to purchase a certificate from a commercial certificate authority to prevent man in the middle attacks (and get rid of annoying browser warning messages).
There are two different methods of installing SSL certificates in SoluSVM depending on if you are using the original Lighttpd web-server or the new Nginx option.
For Lighttpd, you need to place the Base64 encoded DER form of both the private key and the x509 certificate in /usr/local/solusvm/ssl/solusvm.pem and then restart the Lighttpd web-server.
You may need to edit /etc/lighttpd/lighttpd.conf and set “ssl.ca-file” to be the path to the Base64 encoded DER form of the x509 certificate intermediate certificate for your Certificate Authority.
For Nginx, you place the Base64 encoded DER form of both the private key in /usr/local/solusvm/ssl/nginxcert.key and the Base64 encoded DER form of x509 certificate in /usr/local/solusvm/ssl/nginxcert.pem then restart the Nginx web-server.
If you need to include an intermediate certificate for your Certificate Authority, then this also goes in the /usr/local/solusvm/ssl/nginxcert.pem file in Base64 encoded DER form.