Migrating SSL certificates: CPanel, WHM

Possible Scenarios
i) Server load balancing
ii) Moving web sites between servers

Find where the SSL certificates, private keys are installed in the old server and gzip the certs
$ tar -zxcf /tmp/crt.tar.gz /etc/ssl/certs
$ tar -zxcf /tmp/priv.tar.gz /etc/ssl/private

In the new server, extract the certificates and keys to its respective folder location. Edit httpd.conf file and add the following lines

SSLEngine on
SSLCertificateFile /etc/ssl/certs/example.com.crt
SSLCertificateKeyFile /etc/ssl/private/example.com.key
SSLCACertificateFile /etc/ssl/certs/example.com.cabundle
CustomLog /usr/local/apache/domlogs/exampleuser-ssl_log combined

Sample virtual host configuration setting

<VirtualHost xxx.xxx.xxx.xxx:443>
    ServerName subdomain.example.com
    ServerAlias www.subdomain.example.com
    DocumentRoot /home/emaple/public_html
    ScriptAlias /cgi-bin/ /home/example/public_html/cgi-bin/
    SSLEngine on
    SSLCertificateFile /etc/ssl/certs/example.com.crt
    SSLCertificateKeyFile /etc/ssl/private/example.com.key        
   SSLCACertificateFile /etc/ssl/certs/example.com.cabundle    
  CustomLog /usr/local/apache/domlogs/exampleuser-ssl_log combined
    SetEnvIf User-Agent ".*MSIE.*" nokeepalive ssl-unclean-shutdown
    <Directory "/home/example.com/public_html/cgi-bin">
        SSLOptions +StdEnvVars
    </Directory>

    # To customize this VirtualHost use an include file at the following location
    # Include "/usr/local/apache/conf/userdata/ssl/2/exampleuser/example.com/*.conf"
</VirtualHost>

Restart apache
$ /etc/init.d/httpd restart
(or)
$ /sbin/service httpd restart

Note: Once moving the SSL certificates to the new server, you can also use WHM or CPanel to configure the certs.