By default Plesk uses TCP port 8443 to allow access to the control panel, for example: http://server1.domain.net:8443. For security reasons, its recommended to change the default port to a non-standard port number such as 6677.
Parallels Plesk Panel versions 7.x – 8.x use the Apache service with configuration file $PRODUCT_ROOT_D/admin/conf/httpsd.conf. To change the control panel port you need to modify directives Port, Listen and <VirtualHost *:PORT> in the Apache configuration file for the control panel. Once edited you must restart the Plesk control panel:
~# /etc/init.d/psa restart
Stopping Plesk... done
Starting Plesk... done
Please note that none of the ports (21, 22, 23, 25, 53, 80, 110, 443, etc…) used for the standard web hosting services (Apache, POP, SMTP, mySQL, ProFTPd, BIND) can be used.
Parallels Plesk Panel version 9.x uses sw-cp-server instead of Apache. Configuration file of Parallels Plesk Panel is /etc/sw-cp-server/applications.d/plesk.conf. Find the following line in the file and change the port:
$SERVER[“socket”] == “:8443”
After modifying the port you need to restart the sw-cp-server service:
~# /etc/init.d/sw-cp-server restart
Restarting SWsoft control panels server... stale pidfile. [ OK ]
In addition to change the Plesk control panel port (thus obscuring it), its also recommended to restrict access to the port using IPTABLES entries or by using the access manager within the control panel.