Ports and Services
Ports and Services :
20 FTP (Consider SFTP over SSH as is more secure than FTP)
21 FTP (Consider SFTP over SSH as is more secure than FTP)
22 SSH (Consider switching SSH to a different, non-standard port for security reasons)
25 SMTP (some ISPs block port 25 so that a mail client cannot reach the mail server to
send mail)
26 SMTP (alternate SMTP port option – see notes for port 25)
37 rdate (needed to retrieve date and time information)
43 whois (part of generic DNS features)
53 bind (DNS)
80 http (Apache / Web)
110 POP3 (Email)
113 ident (authentication)
143 IMAP (Email)
443 https (Web / HTTP over SSL)
465 SMTP (TLS/SSL)
873 rsync (remote sync)
993 (IMAP SSL)
995 (POP3 SSL)
2083 cPanel (SSL encrypted)
2087 WHM (SSL encrypted)
2089 Licensing (Must be open to contact license server)
2096 Webmail (Horde, Squirrelmail)
3306 MySQL (MySQL remote connections)
