Common Ports
Common TCP ports used by cPanel Servers.
Port: Description:
21 - ftp (File Transfer Protocol)
22 - ssh (secure shell)
25 - smtp (sending e-mail)
53 - DNS (domain look-up)
80 - http (websites)
110 - POP3 (download e-mail to client. Note: use IMAP instead)
143 - IMAP (check e-mail from a client)
443 - https (secure websites)
3306 - MySQL (database)